1001 A+B Format (20分)

PAT (Advanced Level) Practice

题目链接.

• 编程题 1001 A+B Format （20 分）

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1001 A+B Format （20 分）

Calculate a+b and output the sum in standard format – that is, the digits must be separated into groups of three by commas (unless there are less than four digits).
Input Specification:

Each input file contains one test case. Each case contains a pair of integers a and b where −10​6​​≤a,b≤10​6​​. The numbers are separated by a space.
Output Specification:

For each test case, you should output the sum of a and b in one line. The sum must be written in the standard format.

Sample Input:

-1000000 9

Sample Output:

-999,991

参考代码

#include<iostream>
using namespace std;
int main(){
    int a, b;
    cin >> a >> b;
    string s = to_string(a + b);
    int len = s.length();
    for (int i = 0; i < len; i++){
        cout << s[i];
        if (s[i] == '-') continue;
        if ((i+1)%3 == len % 3 && i != len -1) cout << ","; 
    }

    return 0;
}

小伙伴们可以去写更棒的方法哦