hdoj 1002 A + B Problem II(大数加法)

1002 A + B Problem II

#include<bits/stdc++.h>
using namespace std;

const int maxn = 1050;
char a[maxn],b[maxn],c[maxn];

void ADD(char *str1,char *str2,char *str3)
{
int i,j,i1,i2,tmp,carry; //carry用来判断进位
int len1,len2;
len1 = (int)strlen(str1);
len2 = (int)strlen(str2);
char ch;
i1 = len1 - 1;
i2 = len2 - 1;
j = carry = 0;
for(; i1>=0&&i2>=0; ++j,--i1,--i2)//倒序相加
{
tmp=str1[i1]-'0'+str2[i2]-'0'+carry;
carry=tmp/10;
str3[j]=tmp%10+'0';
}
while(i1>=0)
{
tmp=str1[i1--]-'0'+carry;
carry=tmp/10;
str3[j++]=tmp%10+'0';
}
while(i2>=0)
{
tmp=str2[i2--]-'0'+carry;
carry=tmp/10;
str3[j++]=tmp%10+'0';
}
if(carry)
{
str3[j++]=carry+'0';
}
str3[j]='\0';
for(i=0,--j;i<j;++i,--j)//翻转
{
ch = str3[i];
str3[i] = str3[j];
str3[j] = ch;
}
}

int main()
{
int n;
scanf("%d",&n);
for(int i=1;i<=n;i++)
{
scanf("%s %s",&a,&b);
if(i!=1)
printf("\n");
ADD(a,b,c);
printf("Case %d:\n",i);
printf("%s + %s = %s\n",a,b,c);
}
return 0;
}