解いた問題①

問題1

A - Infinite Coins

# include <iostream>
# include <string>
using namespace std;
 
int main(){
  int N,A ;
  cin >> N >> A;
  if(N%500<=A) cout << "Yes" <<endl;
  else cout << "No" << endl;
}

問題2

A - Already 2018

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

int main(){
  string s;
  cin >> s;
  s[3] = '8';
  cout << s << endl;
}

問題3

B - i18n
std::to_string()で数値を文字列に変換できる。
string.length()で文字列の長さを取得できる。

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

int main(){
  string s;
  cin >> s;
  int length = s.length();
  string ans = s[0] + std::to_string(length-2) + s[length-1];
  cout << ans << endl;
}

問題4

B - Shift only

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

int main(){
  int N;
  int A[200];
  cin >> N;
  for(int i=0 ; i<N ; ++i) cin >> A[i];
  int res = 0;
  
  while(true){
    
    bool exist_odd =false;
    
    for(int i=0;i<N;++i){
      if(A[i]%2 != 0) exist_odd = true;
    }
    
    if(exist_odd) break;
    
    for(int i=0;i<N;++i) A[i] /= 2;
    
    ++res;
  }
  
  cout << res <<endl;
}

問題5

B - Maximum Difference

include <iostream>
using namespace std;
 
int main(){
  int N;
  long long int A[201];
  long long int max=0;
  long long int min=1000000000;
  cin >> N;
  for(int i=0; i<N ;++i){
    cin >> A[i];
    if(A[i]>max) max=A[i];
    if(A[i]<min) min=A[i];
  }
  cout << max-min <<endl;
}

問題6

B - OddString

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

int main(){
  string s;
  cin >> s;
  string ans;
  for(int i=0;i<s.length();++i){
    if(i%2==0) ans+=s[i];
  }
  cout << ans << endl;
}

問題7

B - Coins

あ