今天來解YKL09(UVA10931)：Parity

Parity

這題是dec轉成binary
計算binary總共有幾個1

用mod去解

#include <iostream>
using namespace std;

string dectobin(int I){
	string str= "";
	if(I==0)return "0";
	if(I==1)return "1";
	while(I > 0){
		int md=0;
		md = I % 2;
		I = I / 2;
		
		str = to_string(md) + str;
		}
	return str;
}


int main(){
	int I;
	while(cin >> I){
		string str = dectobin(I);
		if(I == 0) break;
		int count=0;
		
		for(int i=0;i <= str.size();i++ ){
			if(str[i] == '1'){
				count++;
			}
		}
		
		cout << "The parity of " << str << " is " << count << " (mod 2)." << endl;
	}	
	return 0;
}