[C++知识库]L1-025 正整数A+B （GPLT）

题目

团体程序设计天梯赛

题解

#include<iostream>
#include<cstdio>
#include<string>

using namespace std;

int is_num(string x){
    if(x[0]=='0')return 0;
    int sum = 0;
    for(auto c:x){
        if('0'<=c&&c<='9'){
            sum = sum*10 + c-'0';
        }else return 0;
    }
    if(1<=sum&&sum<=1000){
        return sum;
    }else return 0;
}

int main()
{
    int sum = 0;
    string A,B;
    cin >> A;
    getchar();
    getline(cin,B);
    int a = is_num(A);
    int b = is_num(B);
    if(a)cout << a;
    else cout << "?";
    cout << " + ";
    if(b)cout << b;
    else cout << "?";
    cout << " = ";
    if(a&&b)cout << a+b;
    else cout << "?";
    return 0;
}