AOJ: Introduction To Programming I の 40 問を C++ で解いた

注意点

コンパイラは C++17 に設定して実施
done is better than perfect の精神で挑戦。
AC コードだが、非効率なところもあるかも。
気になれば後日修正(するかもw)

コメント、アドバイス、大歓迎!!

[第1問 Hello World]

ITP1_1_A.cpp

#include <iostream>
using namespace std;

int main(){
    cout << "Hello World\n";
    return 0;
}

[第2問 X Cubic]

ITP1_1_B.cpp

#include <iostream>
using namespace std;

int main(){
    int N;cin>>N;
    cout << N*N*N << "\n";
    return 0;
}

[第3問 Rectangle]

ITP1_1_C.cpp

#include <iostream>
using namespace std;

int main(){
    int a,b;cin>>a>>b;
    cout << a*b <<" " <<2*a+2*b<<"\n";
    return 0;
}

[第4問 Watch]

ITP1_1_D.cpp

#include <iostream>
using namespace std;

int main(){
    int s;cin>>s;
    int H = (s/3600);
    int M = (s%3600)/60;
    int S = (s%3600)%60;
    cout << H << ":" << M << ":" << S<<"\n";
    return 0;
}

[第5問 Small,Learge,or Equal]

ITP1_2_A.cpp

#include <iostream>
using namespace std;

int main(){
    int a,b;cin>>a>>b;
    if(a==b) cout << "a == b\n";
    else if(a>b) cout << "a > b\n";
    else if(a<b) cout << "a < b\n";
    return 0;
}

[第6問 Range]

ITP1_2_B.cpp

#include <iostream>
using namespace std;

int main() {
    int a, b, c; cin >> a >> b >> c;
    if (a < b  && b < c) cout << "Yes" << "\n";
    else cout << "No" << "\n";
    return 0;
}

[第7問 Sorting Three Numbers]

ITP1_2_C.cpp

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main(){
    vector<int>A(3,0);
    cin>>A[0]>>A[1]>>A[2];
    sort(A.begin(),A.end());
    cout << A[0] <<" "<< A[1] <<" "<< A[2]<<"\n";
    return 0;
}

[第8問 Circle in a Rectangle]

ITP1_2_D.cpp

#include <iostream>
using namespace std;

int main(){
    int W,H,x,y,r;cin>>W>>H>>x>>y>>r;
    if(x>=r && y >= r && r+x <= W && r+y <= H) cout << "Yes\n";
    else cout << "No\n";
    return 0;
}

[第9問 Print Many Hello World]

ITP1_3_A.cpp

#include <iostream>
using namespace std;

int main(){
    for(int i=0;i<1000;i++){
        cout << "Hello World\n";
    }
    return 0;
}

[第10問 Print Test Cases]

ITP1_3_B.cpp

#include <iostream>
#include <vector>
using namespace std;

int main(){
    vector<int>A(10000,0);
    for(int i=0;i<10000;i++){
        cin>>A[i];
        if(A[i]==0)break;
    }
    for(int i=0;i<10000;i++){
        if(A[i] != 0){
            cout << "Case "<<i+1<<": "<<A[i]<<"\n"; 
        }
        else break;
    }
    return 0;
}

[第11問 Swapping Two Numbers]

ITP1_3_C.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
    int a, b;
    vector<pair<int, int>>num;
    while (true) {
        cin >> a >> b;
        if (a == 0 && b == 0) break;
        else num.push_back(pair(min(a, b),max(a,b)));
    }
    for (auto x : num) {
        cout << x.first << " " << x.second << "\n";
    }
    //while (1) {}
    return 0;
}

[第12問 Swapping Two Numbers]

ITP1_3_D.cpp

#include <iostream>
#include <vector>
using namespace std;

int main(){
    int a,b,c;cin>>a>>b>>c;
    
    int cnt=0;
    for(int i=1;i<=c;i++){
        if(c%i == 0 && a<=i && i<=b) cnt++;
    }
    cout << cnt << "\n";
    return 0;
}

[第13問 A/B Problem]

ITP1_4_A.cpp

#include <iostream>
#include <iomanip>
using namespace std;

int main() {
    int a, b; cin >> a >> b;
    cout << a / b << " " << a % b << " ";
    cout << fixed << setprecision(5) << double(a)/double(b)<<"\n";
    //while (1) {}
    return 0;
}

*参考 URL for setprecision => 〇

[第14問 Circle]

ITP1_4_B.cpp

#include <iostream>
#include <iomanip>
using namespace std;
#define PI 3.14159265359

int main() {
    double r; cin >> r;
    cout << fixed << setprecision(5) << PI*r*r<<" ";
    cout << fixed << setprecision(5) << PI*2*r<<"\n";
    //while (1) {}
    return 0;
}

[第15問 Simple Calculator]

ITP1_4_C.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int a, b; char op;
	vector<int>buf;
	while(true){
		cin >> a >> op >> b;
		if (op == '?') break;
		else if (op == '+') buf.push_back(a + b);
		else if (op == '-') buf.push_back(a - b);
		else if (op == '*') buf.push_back(a * b);
		else if (op == '/') buf.push_back(a / b);
	}
	for (auto x : buf)
		cout << x << "\n";
	return 0;
}

[第16問 Min,Max and Sum]

ITP1_4_D.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int N; cin >> N;
	vector<int>A(N, 0);

	int MIN = 1000000, MAX = -1000000;long long SUM = 0;
	for (int i = 0; i < N; i++){
		cin >> A[i];
		SUM += A[i]; 
		MIN = min(MIN, A[i]);
		MAX = max(MAX, A[i]);
	}
	cout << MIN << " " << MAX << " " << SUM << "\n";
	//while (1) {}
	return 0;
}

[第17問 Print a Rectangle]

入力を受けきってから出力しないと WA となるようです。

ITP1_5_A.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int H, W;
	vector<pair<int, int>>num;
    //---> input
	while (true) {
		cin >> H >> W;
		if (H == 0 && W == 0) 
			break;
		num.push_back(pair(H, W));
	}

    //----> output
	for (auto n : num) {
		vector<string>S; string s;
		for (int h = 0; h < n.first; h++) {
			for (int w = 0; w < n.second; w++) {
				s += "#";
			}
			S.push_back(s);
			s = "";
		}
        //---> print 
		for (auto z : S)
			cout << z << "\n";
		cout << "\n";
	}

	//while (1) {}
	return 0;
}

[第18問 Print a Frame]

問17 の解をカスタム

ITP1_5_B.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int H, W;
	vector<pair<int, int>>num;
	while (true) {
		cin >> H >> W;
		if (H == 0 && W == 0) 
			break;
		num.push_back(pair(H, W));
	}

	for (auto n : num) {
		vector<string>S; string s;
		for (int h = 0; h < n.first; h++) {
			for (int w = 0; w < n.second; w++) {
				if ((h == 0 || h == n.first - 1))       //←custom point
					s += "#";                           //←
				else if ((w == 0 || w == n.second - 1)) //←
					s += "#";                           //←
				else                                    //←
					s += ".";                           //←
			}
			S.push_back(s);
			s = "";
		}
		for (auto z : S)
			cout << z << "\n";
		cout << "\n";
	}

	while (1) {}
	return 0;
}

[第19問 Print a Chessboard]

問17をカスタム

ITP1_5_C.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int H, W;
	vector<pair<int, int>>num;
	while (true) {
		cin >> H >> W;
		if (H == 0 && W == 0) 
			break;
		num.push_back(pair(H, W));
	}

	for (auto n : num) {
		vector<string>S; string s;
		for (int h = 0; h < n.first; h++) {
			for (int w = 0; w < n.second; w++) {
				if (h % 2 == 0) {               //<=custom point
					if (w % 2 == 0)             //<=
						s += "#";               //<=
					else                        //<=
						s += ".";               //<=
				}                               //<=
				else {                          //<=
					if (w % 2 == 0)             //<=
						s += ".";               //<=
					else                        //<=
						s += "#";               //<=
				}                               //<=
			}
			S.push_back(s);
			s = "";
		}
		for (auto z : S)
			cout << z << "\n";
		cout << "\n";
	}

	while (1) {}
	return 0;
}

[第20問 Structured Programming]

goto 文の理解は cout でコメントを置きながら読むと、つかみ易い。

ITP1_5_D.cpp

#include <iostream>
using namespace std;

int main() {
    int n; cin >> n;
    for (int i = 1; i <= n; i++) {
        int N = i;
        if (N % 3 == 0)
            cout << " " << i;
        else {
            while (N > 0) {
                if (N % 10 == 3){
                    cout << " " << i;
                    break;
                }
                N /= 10;
            }
        }
    }
    //while (1) {}
    return 0;
}

[第21問 Reversing Numbers]

sort(**begin(),**end(),greater()) が通用しない

ITP1_6_A.cpp

#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

int main() {
    int N; cin >> N;
    vector<int>A(N, 0);
    for (int i = 0; i < N; i++) {
        cin >> A[i];
    }
    reverse(A.begin(), A.end());
    //sort(A.begin(), A.end(),greater<int>());
    for (int i = 0; i < N; i++) {
        if (i != N - 1) {
            cout << A[i] << " ";
        }
        else {
            cout << A[i]<<"\n";
        }
    }
    //while (1) {}
    return 0;
}

[第22問 Finding Missing Cards]

ITP1_6_B.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int N; cin >> N;
	vector<vector<int>>cards(4, vector<int>(14, 0));
	char K; int num;

	for (int i = 0; i < N; i++) {
		cin >> K >> num;
		if (K == 'S')
			cards[0][num] = 1;
		else if(K == 'H')
			cards[1][num] = 1;
		else if (K == 'C')
			cards[2][num] = 1;
		else if (K == 'D')
			cards[3][num] = 1;
	}


	//cout << "\n";

	/*
	for (int i = 1; i < 14; i++)
		cout << cards[0][i] << " ";
	cout << "\n";
	*/

	
	for (int i = 0; i < 4; i++) {
		for (int l = 1; l <= 13; l++) {
			if (cards[i][l] == 0) {
				if (i == 0)
					cout << "S " << l << "\n";
				else if (i == 1)
					cout << "H " << l << "\n";
				else if (i == 2)
					cout << "C " << l << "\n";
				else if (i == 3)
					cout << "D " << l << "\n";
			}
				
		}
	}
	
	//while (1) {}
	return 0;

}

[第23問 Official House]

ITP1_6_C.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int N; cin >> N;
	vector<vector<int>>map(12, vector<int>(10, 0));
	int b, f, r, v;
	for (int i = 0; i < N; i++) {
		cin >> b >> f >> r >> v;
		b = (b - 1) * 3;
		map[b + f-1][r - 1] += v;
	}

	//cout << "\n";

	for (int h = 0; h < 12; h++) {
		for (int w = 0; w < 10; w++) {
			cout << " " << map[h][w];
		}
		cout << "\n";
		if (h == 2 || h == 5 || h == 8)
			cout << "####################\n";
	}

	//while (1) {}
	return 0;

}

[第24問 Matrix Vector Multiplication]

ITP1_6_D.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int n, m; cin >> n >> m;

	vector<vector<int>>A(n,vector<int>(m,0));
	for (int h = 0; h < n; h++) {
		for (int w = 0; w < m; w++) {
			cin >> A[h][w];
		}
	}
	vector<int>B(m, 0);
	for (int i = 0; i < m; i++)
		cin >> B[i];

	for (int h = 0; h < n; h++) {
		int ans = 0;
		for (int w = 0; w < m; w++) {
			ans += A[h][w]*B[w];
		}
		cout << ans << "\n";
	}
	//while (1) {}
	return 0;
}

[第25問 Grading]

ITP1_7_A.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int m, f, r;
	vector<string>rank;
	while (true) {
		cin >> m >> f >> r;
		if (m == -1 && f == -1 && r == -1) break;
		if (m == -1 || f == -1) rank.push_back("F");
		else if (m + f >= 80) rank.push_back("A");
		else if (65 <= m + f && m + f < 80) rank.push_back("B");
		else if (50 <= m + f && m + f < 65) rank.push_back("C");
		else if (30 <= m + f && m + f < 50) {
			if (r >= 50) rank.push_back("C");
			else rank.push_back("D");}
		else if (m + f < 30) rank.push_back("F");

	}
	for (auto r : rank)
		cout << r << "\n";

	//while (1) {}
	return 0;
}

[第26問 How many ways?]

ITP1_7_B.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int n,x,ans;
	vector<int>N;
	while (true) {
		cin >> n>>x;

		if (n == 0 && x == 0) break;
		ans = 0;
		for (int i = 1; i <= n - 2; i++) {
			for (int j = i + 1; j <= n - 1; j++) {
				for (int k = j + 1; k <= n; k++) {
					if (i + j + k == x) {
						//cout << i << " " << j << " " << k << "\n";
						ans++; }
				}
			}
		}
		N.push_back(ans);
	}
	for (auto n : N)
		cout << n << "\n";

	//while (1) {}
	return 0;
}

[第27問 Spreadsheet]

ITP1_7_C.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int H, W; cin >> H >> W;
	vector<vector<int>>S(H + 1, vector<int>(W + 1, 0));

	for (int h = 0; h < H; h++) {
		for (int w = 0; w < W; w++) {
			cin >> S[h][w];
		}
	}

	for (int h = 0; h < H ; h++) {
		int Wsum = 0;
		for (int w = 0; w < W; w++)
			Wsum += S[h][w];
		S[h][W] = Wsum;
		Wsum = 0;
	}

	for (int w = 0; w <= W; w++) {
		int Hsum = 0;
		for (int h = 0; h < H; h++) 
			Hsum += S[h][w];
		S[H][w] = Hsum;
		Hsum = 0;
	}
	
	for (int h = 0; h <= H; h++) {
		for (int w = 0; w <= W; w++) {
			if(w==W)
				cout << S[h][w] << "\n";
			else
				cout << S[h][w] << " ";
		}
	}

	//while (1) {}
	return 0;
}

[第28問 Matrix Multiplication]

ITP1_7_D.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int n, m, l; cin >> n >> m >> l;
	vector<vector<int>>A(n, vector<int>(m, 0));
	vector<vector<int>>B(m, vector<int>(l, 0));
	vector<vector<long long>>C(n, vector<long long>(l, 0));

	for (int h= 0; h < n; h++) {
		for (int w = 0; w < m; w++)
			cin >> A[h][w];
	}

	for (int h = 0; h < m; h++) {
		for (int w = 0; w < l; w++)
			cin >> B[h][w];
	}

		for(int bw = 0;bw<l;bw++){
			for(int ah=0;ah<n;ah++){
				for (int bh = 0; bh < m; bh++) {
					C[ah][bw] += B[bh][bw] * A[ah][bh];
				}
			}
		}
	
	for (int h = 0; h < n; h++) {
		for (int w = 0; w < l; w++) {
			if(w != l-1) cout << C[h][w] << " ";
			else cout << C[h][w] << "\n";
		}
	}

	//while (1) {}

	return 0;

}

[第29問 Toggling Cases]

ITP1_8_A.cpp

#include <iostream>
#include <string>
#include <vector>
using namespace std;

int main() {
	
	string s;
	getline(cin, s);

	for (auto x : s) {
		if (islower(x)) 
			x = toupper(x); 
		else if (isupper(x)) 
			x = tolower(x);
		cout << x;
	}cout << "\n";

	//while (1) {}
	return 0;
}

[第30問 Sum of Numbers]

ITP1_8_B.cpp

#include <iostream>
#include <vector>
using namespace std;

int main() {
	string n; int sum = 0;
	vector<int>num;

	while(true){
		cin >> n;
		if (n !="0") {
			for (int i = 0; i < n.size(); i++) {
				sum += int(n[i] - '0');
			}
			num.push_back(sum);
			sum = 0;
		}
		else
			break;
	}

	for (auto x : num)
		cout << x << "\n";

	//while (1) {}
	return 0;
}

[第31問 Counting Characters]

VScode で事前確認してからブラウザに入力している。
VScode の場合は コードを F5 で実行 => enter=> ctrl+z(EOF) で
初めて動作確認できる。

ITP1_8_C.cpp

#include <iostream>
#include <algorithm>
#include <string>
#include <map>
using namespace std;

int main() {
    
    string S,a;
    while (cin>>S) {
        a+=S;
    }
    transform(a.begin(), a.end(),a.begin(), ::tolower);
    map<char,int>n;
    for (char c = 'a'; c <= 'z'; c++) n[c] = 0;
    for (int i = 0; i < a.size(); i++) {
        if(n.count(a[i])!=0) n[a[i]]++;
    }
    for (auto x:n)
        cout << x.first << " : " << x.second <<"\n";

    //while (1) {}
    return 0;
}

[第32問 Ring]

ITP1_8_D.cpp

#include <iostream>
#include <string>
using namespace std;

int main() {
	string S, P; cin >> S >> P;
	
	bool flag = false;
	for (int i = 0; i < S.size() - P.size()+1; i++) {
		//cout << S.substr(i, P.size()) << "\n";
		if (S.substr(i, P.size()) == P)
			flag = true;
	}
	//cout << "\n";
	string M;
	for (int i = S.size() - P.size() + 1; i < S.size(); i++) {
		M = S.substr(i, S.size() - i) + S.substr(0, P.size() - (S.size() - i));
		//cout << M << "\n";
		if (M == P)
			flag = true;
	}
	if (flag) cout << "Yes\n";
	else cout << "No\n";

	//while (1) {}
	return 0;
}

[第33問 Finding a Word]

ITP1_9_A.cpp

#include <iostream>
#include <algorithm>
#include <string>
#include <map>
using namespace std;

int main() {
	string W,S; cin >> W;
	map<string, int>nums;

	while (true) {

		cin >> S;
		if (S != "END_OF_TEXT") {
			transform(S.begin(), S.end(), S.begin(), ::tolower);
			nums[S]++;
		}
		else
			break;

	}

	cout << nums[W] <<"\n";

	//while (1) {}
	return 0;
}

[第34問 Shuffle]

ITP1_9_B.cpp

#include <iostream>
#include <string>
#include <vector>
using namespace std;

int main() {
	string S; int m, h;
	vector<string>buff;

	while(true){
		cin >> S; if (S == "-") break;
		cin >> m;

		for (int i = 0; i < m; i++) {
			cin >> h;
			//cout << S.substr(h, S.size() - h) << " " << S.substr(0, h) << "\n";
			S =  S.substr(h, S.size() - h) + S.substr(0, h);
		}
		buff.push_back(S);
	}

	for (auto x : buff)
		cout << x << "\n";

	//while (1) {}
	return 0;
}

[第35問 Card Game]

ITP1_9_C.cpp

#include <iostream>
using namespace std;

int main() {
	int N; cin >> N;
	int SA = 0, SB = 0;
	string cA, cB;

	for (int i = 0; i < N; i++) {
		cin >> cA >> cB;
		SA += 3*(cA > cB) + (cA == cB);
		SB += 3*(cB > cA) + (cA == cB);
	}

	cout << SA << " " << SB << "\n";
	//while (1) {}
	return 0;
}

[第36問 Transformation]

勉強になりました。

ITP1_9_D.cpp

#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
using namespace std;

int main() {
	string S; int N; cin >> S >> N;
	string CMD, word; int st, ed;
	vector<string>ans;
	for (int i = 0; i < N; i++) {
		cin >> CMD >> st >> ed;
		if (CMD == "replace") {
			cin >> word;
			S =S.substr(0, st) + word + S.substr(ed+1, S.size() - ed-1);
			//cout << S << "\n";
		}
		
		else if (CMD == "reverse") {
			reverse(S.begin()+st, S.end()-(S.size()-ed-1));
			//cout << S << "\n";
		}
		
		else {
			ans.push_back(S.substr(st, ed-st+1));
			//cout << S.substr(st, ed+1) << "\n";
		}
		
	}

	//cout << "\n";
	for (auto x : ans)
		cout << x << "\n";

	//while (1) {}
	return 0;
}

[第37問 Distance]

ITP1_10_A.cpp

#include <iostream>
#include <iomanip>
#include <math.h>
using namespace std;

int main() {
	double x1, y1, x2, y2;
	cin >> x1 >> y1 >> x2 >> y2;

	double ans = pow((pow((x1 - x2),2) + pow((y1 - y2),2)),0.5);
	cout << fixed << ans << setprecision(5);
	//while (1) {}
	return 0;
}

[第38問 Traiangle]

ITP1_10_B.cpp

#include <iostream>
#include <iomanip>
#include <math.h>
using namespace std;
#define PI 3.14159265359

int main() {
	double a, b, C; cin >> a >> b >> C;
	double S = (a * sin((PI / 180) * C) * b) / 2;
	double L = a + b + pow(a * a + b * b - 2 * a * b * cos((PI / 180) * C),0.5);
	double h = b * sin((PI / 180) * C);

	cout << fixed << S << "\n" << L << "\n" << h <<setprecision(5) << "\n";
	//while (1) {}
	return 0;
}

[第39問 Standard Deviation]

ITP1_10_C.cpp

#include <iostream>
#include <iomanip>
#include <vector>
#include <math.h>
using namespace std;
#define PI 3.14159265359

int main() {
	double n;
	vector<double>buff;
	while (true) {
		cin >> n;
		if (n == 0)break;

		double m = 0; vector<double>s(n, 0);
		for (int i = 0; i < n; i++) {
			cin >> s[i];
			m += s[i];
		}m /= n;

		double num = 0;
		for (auto x : s)
			num += pow((x - m), 2);
		num /= n;
		buff.push_back(num);
	}
	//cout << "\n";
	for(auto y:buff)
		cout << fixed << pow(y, 0.5) << setprecision(4) << "\n";
	
//	while (1) {}
	return 0;
}

[第40問 Distance II]

※math.h よりも cmath の方が安定。

ITP1_10_D.cpp

#include <iostream>
#include <iomanip>
#include <vector>
#include <cmath>//    <= ※
using namespace std;

int main() {
	int n; cin >> n;
	vector<double>x(n, 0);
	vector<double>y(n, 0);
	for (int i = 0; i < n; i++) cin >> x[i];
	for (int i = 0; i < n; i++) cin >> y[i];

	double p1 = 0, p2 = 0, p3 = 0 , pm = 0;
	for (int i = 0; i < n; i++) {
		p1 += abs(x[i] - y[i]);
		p2 += pow(abs(x[i] - y[i]), 2);
		p3 += pow(abs(x[i] - y[i]), 3);
		pm = max(pm, abs(x[i] - y[i]));
	}
	p2 = pow(p2, (double)1/(double)2);
	p3 = pow(p3, (double)1/(double)3);
	cout << fixed << setprecision(5) << p1 << "\n" << p2 << "\n" << p3 << "\n" << pm << "\n";

	//while (1) {}
	return 0;
}