Pat甲级 1001 A+B Format

题目网址
https://pintia.cn/problem-sets/994805342720868352/problems/994805528788582400

思路

a+b按照一定格式输出,都不是大数,直接加就完事儿了,注意下结果为0的情况就好.我的代码是为了练习vector容器特意写成这样的,更简单的思路应该是把相加的数字转为string,然后判断输出逗号.

代码

#include <iostream>
#include <cmath>
#include <vector>
#include <algorithm>

using namespace std;

vector<char> v;

int main() {
    int a;
    int b;
    int sum;
    int cnt = 1;

    cin >> a >> b;
    sum = a + b;
    if (sum < 0)
        cout << "-";
    sum = abs(sum);
    if (sum == 0) {
        cout << 0 << endl;
        return 0;
    }
    while (sum > 0) {
        int t = sum % 10;
        sum /= 10;
        v.push_back(t + '0');
        if (cnt == 3) {
            v.push_back(',');
            cnt = 0;
        }
        cnt ++;
    }
    if (v.back() == ',')
        v.pop_back();
    reverse(v.begin(), v.end());
    for (auto i : v)
        cout << i;
    return 0;
}
}