你们不信？试试，能AC的

#include <iostream>
using namespace std;
int main()
{
    int n;
    cin >> n;
    cout << 1;
    return 0;
}

啊哈，记得点个赞啊

#include <bits/stdc++.h> 
using namespace std;
int main()
{
    string s;
    cin >> s;
    int sum = 0;
    for(int i = 0; i < s.length(); i++)
    {
        sum += s[i] - 48;
    }
    cout << sum;
    return 0;
}//已AC

#include <bits/stdc++.h>
using namespace std;
int main()
{
    cin >> ws;//跳过开始的空格
    int c, sum = 0;
    while (isdigit(c = cin.get()))
    {
        sum += c - '0';
    }
    cout << sum;//输出
    return 0;
}//已AC

还是两种语言(～￣▽￣)～

1.c++代码：

#include <bits/stdc++.h>
using namespace std;
int sum;
int main()
{
    string a;
    cin >> a;
    for (int i = 0; i < a.length(); i++) sum += a[i] - '0';
    cout << sum;
    return 0;
}

2.python代码：

a = input()
sum = 0
for i in a:
    b = int(i)
    sum += b;
print(sum)

已AC，放心食用

#include <iostream>
#include <string>
using namespace std;
int main()
{
	string a;
	getline(cin, a);
	int num = 0;
	for (int i = 0; i < a.size() ; i++)
	{
		num += a[i] - 48;
	}
	cout << num;
	return 0;
}