忽略了零的时候的情况啊!!!
题目连接http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=1047
#include<stdio.h>
#include<math.h>
#include<string.h>
char a[300],b[300];
int f[600],count;
int main()
{
while(scanf("%s%s",a,b) == 2)
{
int len1,len2,i,j,m,max,wei,k;
len1 = strlen(a);
len2 = strlen(b);
for(i = 0;i < 600-1;i++)
f[i] = 0;
for(i = len2-1;i >= 0;i--)
{
count = len2-i-1;
m = wei = 0;
for(j = len1-1;j >= 0;j--)
{
m = (a[j]-'0')*(b[i]-'0')+f[count]+wei;
f[count++] = m%10;
wei = m/10;
}
if(wei)
f[count++] = wei;
}
for(i = count-1;i >0 ;i--)
{
if(f[i])
break;
}
for(;i >= 0;i--)
printf("%d",f[i]);
puts("");
}
return 0;
}