题解 | #高精度整数加法#

#include <stdio.h>
#include <string.h>

int main() {
    char a[10000], b[10000];
    memset(a, 0, sizeof(a));
    memset(b, 0, sizeof(b));
    scanf("%s",a);
    scanf("%s",b);
    /**逆序字符串*/
    int cntStr = strlen(a)%2==0?strlen(a)/2:(strlen(a)-1)/2;
    for(int i=0;i<cntStr;i++){
        char temp = a[strlen(a)-i-1];
        a[strlen(a)-i-1] = a[i];
        a[i] = temp;
    }
    cntStr = strlen(b)%2==0?strlen(b)/2:(strlen(b)-1)/2;
    for(int i=0;i<cntStr;i++){
        char temp = b[strlen(b)-i-1];
        b[strlen(b)-i-1] = b[i];
        b[i] = temp;
    }
    // printf("%s\n", a);
    // printf("%s\n", b);
    /*相加**/
    cntStr = strlen(b) > strlen(a)?strlen(b):strlen(a);
    int flag = 0;
    for(int i=0;i<cntStr;i++){
        int aNumber = a[i] >= '0' ?  a[i]-'0':a[i];
        int bNumber = b[i] >= '0' ?  b[i]-'0':b[i];
        if(aNumber + bNumber + flag >=10){
            a[i] = aNumber + bNumber + flag - 10 + '0';
            flag = 1;
        }else {
            a[i] = aNumber + bNumber + flag + '0' ; 
            flag = 0; 
        }
    }
    if(flag) {
        a[cntStr] = '1';
        a[cntStr+1] = '\0';
    }

    for(int i=strlen(a)-1;i>=0;i--){
        printf("%c",a[i]);
    }
    return 0;
}