windowsでiverilog その201

概要　

windowsでiverilogやってみた。
練習問題やってみた。

練習問題

atcoderを解け。
ABC 049 C - Daydream
文字列Sが、'dream','dreamer','erase','eraser'の組み合わせで作れるかどうかを判定する。

投入するソース

erasedream

期待値

YES

サンプルコード

module test;
	integer stdin = 'h8000_0000;
	integer a,
		b,
		c,
		ch,
		v,
		p;
	reg [7:0] pc;
	reg [7:0] str[0:19];
	logic [6:0][7:0] str0 = "remaerd";
	logic [5:0][7:0] str1 = "resare";
	logic [4:0][7:0] str2 = "maerd";
	logic [4:0][7:0] str3 = "esare";
	always #1
	begin
		case(pc)
		10:
		begin
			ch = $fgetc(stdin);
			pc <= 20;
		end
		20:
		begin
			str[v] = ch;
			if (ch == 'ha)
			begin
				a = 0;
				b = 0;
				p = 7;
				pc <= 30;
			end
			else
			begin
				v++;
				pc <= 10;
			end
		end
		30:
		begin
			//$display("%s %s", str[a], str0[b]);
			if (str[a] == str0[b])
			begin
				a = a + 1;
				b = b + 1;
				if (b == p)
				begin
					//$display("--ok0");
					if (a == v)
					begin
						pc <= 150;
					end
					else
					begin
						b = 0;
						p = 7;
						pc <= 30;
					end
				end
				else
				begin
					pc <= 30;
				end
			end
			else
			begin
				//$display("--pass0");
				a = a - b;
				b = 0;
				p = 6;
				pc <= 40;
			end
		end
		40:
		begin
			//$display("%s %s", str[a], str1[b]);
			if (str[a] == str1[b])
			begin
				a = a + 1;
				b = b + 1;
				if (b == p)
				begin
					//$display("--ok1");
					if (a == v)
					begin
						pc <= 150;
					end
					else
					begin
						b = 0;
						p = 7;
						pc <= 30;
					end
				end
				else
				begin
					pc <= 40;
				end
			end
			else
			begin
				//$display("--pass1");
				a = a - b;
				b = 0;
				p = 5;
				pc <= 50;
			end
		end
		50:
		begin
			//$display("%s %s", str[a], str2[b]);
			if (str[a] == str2[b])
			begin
				a = a + 1;
				b = b + 1;
				if (b == p)
				begin
					//$display("--ok2");
					if (a == v)
					begin
						pc <= 150;
					end
					else
					begin
						b = 0;
						p = 7;
						pc <= 30;
					end
				end
				else
				begin
					pc <= 50;
				end
			end
			else
			begin
				//$display("--pass2");
				a = a - b;
				b = 0;
				p = 5;
				pc <= 60;
			end
		end
		60:
		begin
			//$display("%s %s", str[a], str3[b]);
			if (str[a] == str3[b])
			begin
				a = a + 1;
				b = b + 1;
				if (b == p)
				begin
					//$display("--ok3");
					if (a == v)
					begin
						pc <= 150;
					end
					else
					begin
						b = 0;
						p = 7;
						pc <= 30;
					end
				end
				else
				begin
					pc <= 60;
				end
			end
			else
			begin
				//$display("--pass3");
				pc <= 130;
			end
		end
		130:
		begin
			pc <= 140;
			if (a == p)
			begin
				pc <= 30;
			end
			if (a == v)
			begin
				pc <= 150;
			end
		end
		140:
		begin
			$write("NO");
			pc <= 160;
		end
		150:
		begin
			$write("YES");
			pc <= 160;
		end
		160:
		begin
			$finish(0);
		end
		endcase
	end
	initial
	begin
		//$monitor(" %d", pc);
		//$display("str=%s", str[0]);
		//$display("str0=%s", str0[0]);
		pc <= 10;
		a = 0;
		b = 0;
		v = 0;
		p = 0;
		#200
			$finish(0);
	end
endmodule

実行結果

>vvp a.out
erasedream
YES

以上。