poj 3673

小水一道

有两个数 A and B (1 ≤ A, B ≤ 1,000,000,000), 作如下运算,例如：123*45 is equal to 1*4 + 1*5 + 2*4 + 2*5 + 3*4 + 3*5 = 54. 

#include <cstdio>#include <iostream>#include <string.h>#include <stdlib.h>#include <fstream>#include <math.h>#include <algorithm>#define INF 0x3f3f3f3fusing namespace std;char a[11],b[11];int sum;int main(){//freopen ("input.txt","r",stdin);scanf("%s %s",a,b);sum=0;int l1=strlen(a),l2=strlen(b);for(int i=0;i<l1;i++)for(int j=0;j<l2;j++)sum+=(a[i]-'0')*(b[j]-'0');cout<<sum<<endl;return 0;}