沙发

#include<bits/stdc++.h>
using namespace std;

int main()
{
    long long sum;
    cin>>sum;
    char fuhao;
    while(cin>>fuhao)
        {
            int num;
            cin>>num;
            if(fuhao=='+')
                sum+=num;
            else
                sum-=num;
        }
    cout<<sum;
}