FZU1453

#include<stdio.h>#include<string.h>int sum[165];void mul(char aa[],char bb[],int len1,int len2){int a[85]={0},b[85]={0};int i,j;for(i=0;i<len1;i++){a[len1-1-i]=aa[i]-'0';}for(i=0;i<len2;i++){b[len2-1-i]=bb[i]-'0';}for(i=0;i<len1;i++){for(j=0;j<len2;j++){sum[i+j]+=a[i]*b[j];}}for(i=0;i<(len1+len2-1);i++){if(sum[i]>=10){sum[i+1]+=sum[i]/10;sum[i]%=10;}}}int main(){char aa[85],bb[85];int i,len1,len2,flag;while(~scanf("%s",aa)){scanf("%s",bb);memset(sum,0,sizeof(sum));len1=strlen(aa);    len2=strlen(bb);mul(aa,bb,len1,len2);flag=0;for(i=(len1+len2-1);i>=0;i--){if(sum[i]!=0&&flag==0) flag=1;if(flag){printf("%d",sum[i]);}}if(flag==0) printf("0");printf("\n");memset(aa,0,sizeof(aa));memset(bb,0,sizeof(bb));}return 0;}