题解 | #特殊乘法#

#include<cstdio>
#include<vector>
using namespace std;
int main(){
	long long n, m;
	vector<int>vec1;
	vector<int>vec2;
	while (scanf("%lld %lld", &n, &m) != EOF){
		int x, y;
		while (n != 0){
			x = n % 10;
			vec1.push_back(x);
			n = n / 10;
		}
		while (m != 0){
			y = m % 10;
			vec2.push_back(y);
			m = m / 10;
		}
		int sum = 0;
		for (int i = 0; i < vec1.size(); i++){
			for (int j = 0; j < vec2.size(); j++){
				sum = vec1[i] * vec2[j] + sum;
			}
		}
		printf("%d", sum);
	}
}