12月3日a*b

Description

Now Give you two integers A and B , please caculate the value of A multiply B.Attation: A、B and are all non-negative numbers.

Input

Each line contain two integers A and B. Procss to end of file.(EOF)

Output

For each case, Please output the value of A multiply B

Sample Input 1

3 2
1 5

Sample Output 1

6
5

一位大佬的代码

#include<stdio.h>
#include<string.h>
#include<math.h>
#define N 1005
char a[N],b[N];
int s1[N],s2[N],s3[N*N];
int main()
{
    int len1,len2,max,i,j;
    while(scanf("%s%s",a,b)!=EOF)
    {
        memset(s1,0,sizeof(s1));
        memset(s2,0,sizeof(s2));
        memset(s3,0,sizeof(s3));
        len1=strlen(a);
        len2=strlen(b);
        max=0;
        max=len1+len2;
        for(i=0,j=len1-1; i<len1; i++,j--)
            s1[i]=a[j]-'0';
        for(i=0,j=len2-1; i<len2; i++,j--)
            s2[i]=b[j]-'0';
        for(i=0; i<len1; i++)
            for(j=0; j<len2; j++)
                s3[i+j]+=s1[i]*s2[j];
        for(i=0; i<max; i++)
        {
            if(s3[i]>=10)
            {
                s3[i+1]+=s3[i]/10;
                s3[i]%=10;
            }
        }
        while(s3[max-1]==0)
        {
            if(s3[max-1]==0)
                max--;
        }
        for(i=max-1; i>=0; i--)
            printf("%d",s3[i]);
        printf("\n");
    }
    return 0;
}