问题 A: a+b

#include <cstdio>
#include <cstring>


using namespace std;

struct big_number {
    int d[1001], len;

    big_number() {
        memset(d, 0, sizeof(d));
        len = 0;
    }
};

big_number change(char s[]) {
    big_number ans;
    int len = strlen(s);
    ans.len = len;
    for (int i = 0; i < len; ++i) {
        ans.d[i] = s[len - i - 1]-'0';
    }
    return ans;
}

big_number b_plus(const big_number &a, const big_number &b) {

    big_number ans;
    int carry = 0;
    int i;
    for (i = 0; i < a.len || i < b.len; ++i) {
        int temp = a.d[i] + b.d[i] + carry;
        carry = temp / 10;
        ans.d[i] = temp % 10;
    }
    if (carry != 0) ans.d[i++] = carry;
    ans.len = i;
    return ans;

}

int main() {

    char s1[1001], s2[1001];

    while (scanf("%s %s", s1, s2) != EOF) {
        big_number a = change(s1);
        big_number b = change(s2);
        big_number ans = b_plus(a, b);

        for (int i = ans.len - 1; i >= 0; --i) {
            printf("%d", ans.d[i]);
        }
        printf("\n");

    }

    return 0;
}

问题 A: a+b

原文：https://www.cnblogs.com/ailinal/p/12377777.html