这个大数加法错哪里了？

[firsun]

哪些部分有问题啊？

#include<stdio.h>
#include<string.h>
void swapStr(char *a)
{
    short i;
    int len;
    len = strlen(a);
    for(i=0;i<len/2;i++)
    {
        a[i]^=a[len-i-1];
        a[len-i-1]^=a[i];
        a[i]^=a[len-i-1];
    }
}

int main()
{
    short T;
    short temp;
    int lena,lenb,i,carry;
    char a[1002],b[1002],c[1002];
    scanf("%d",&T);
    for(int j=1;j<=T;j++)
    {
        i = 0;
        carry = 0;
        memset(a,0,1002);
        memset(b,0,1002);
        memset(c,0,1002);
        scanf("%s%s",a,b);
        lena = strlen(a);
        lenb = strlen(b);
        while(lena>0&&lenb>0)
        {
            temp = a[lena-1]-'0'+ b[lenb-1]-'0'+carry;
            c[i] = temp%10+'0';
            carry = temp/10;
            lena--;
            lenb--;
            i++;
        }
        while(lena>0)
        {
            temp = a[lena-1]+carry-'0';
            c[i] = temp%10+'0';
            carry = temp/10;
            lena--;
            i++;
        }
        while(lenb>0)
        {
            temp = b[lenb-1]+carry-'0';
            c[i] = temp%10+'0';
            carry = temp/10;
            lenb--;
            i++;
        }
        if(carry)
            c[i] = carry+'0';
        swapStr(c);
        printf("case %d:\n",j);
        printf("%s + %s = %s\n\n",a,b,c);
    }
    return 0;
}

[FancyMouse]

c你没有在最后加上'\0'……

[赵4老师]

#include <stdio.h>
#include <string.h>
#define MAXLEN 1000
char a1[MAXLEN];
char a2[MAXLEN];
static int v1[MAXLEN];
static int v2[MAXLEN];
static int v3[MAXLEN];
int i,j,n,L,z;
void main(void) {
    scanf("%d",&n);
    for (j=0;j<n;j++) {
        scanf("%s%s",a1,a2);

        L=strlen(a1);
        for (i=0;i<L;i++) v1[i]=a1[L-1-i]-'0';

        L=strlen(a2);
        for (i=0;i<L;i++) v2[i]=a2[L-1-i]-'0';

        for (i=0;i<MAXLEN;i++) v3[i]=v1[i]+v2[i];

        for (i=0;i<MAXLEN;i++) {
            if (v3[i]>=10) {
                v3[i+1]+=v3[i]/10;
                v3[i]=v3[i]%10;
            }
        }

        printf("Case %d:\n", j+1);
        printf("%s + %s = ", a1, a2);

        z=0;
        for (i=MAXLEN-1;i>=0;i--) {
            if (z==0) {
                if (v3[i]!=0) {
                    printf("%d",v3[i]);
                    z=1;
                }
            } else {
                printf("%d",v3[i]);
            }
        }
        if (z==0) printf("0");

        printf("\n");
    }
}
//Sample Input
//3
//0 0
//1 2
//112233445566778899 998877665544332211
//
//Sample Output
//Case 1:
//0 + 0 = 0
//Case 2:
//1 + 2 = 3
//Case 3:
//112233445566778899 + 998877665544332211 = 1111111111111111110

[FserSuN]

你的代码没有错误！ 但是如果输入为00000000001 + 10 这种带有前导0的数据输出上再做下处理就可以了。 还有你每次初始化 memset(c,0,1002); 所以不用考虑最后 + '\0'的问题。