找出1000内的所有“完数”并且按格式输出其因子(C++)

一个数如果恰好等于它的因子之和,这个数就被称为“完数”。

找出1000之内的所有完数,并且按下面格式输出其因子:

6,its factors are 1,2,3

#include
#include
using namespace std;
int main() {
	for (int i = 1; i < 1001; i++) {
		int y = 0;
		for (int x = 1; x < i; x++) {
			if (i % x == 0) {
				y+=x;
			}
		}
		if (y == i) {
			int a = 1;
			cout << i <<",its factors are ";
			for (int b = 1; b < i; b++) {
				if (i % b == 0&&a==1) {						
					cout << b;
					a = 0;
				}
				else if(i % b == 0){
					cout << ',' << b;
				}
			}		
			cout << endl;
		}
	}
	return 0;	
}

运行结果:

6,its factors are 1,2,3
28,its factors are 1,2,4,7,14
496,its factors are 1,2,4,8,16,31,62,124,248

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