C :

#include<stdio.h>
#include<stdlib.h>
int main()
{
    char d,c[10];
    int a,b,e,n=0;
    while((scanf("%d%c%d=%s",&a,&d,&b,c)!=EOF))
    {
        if(c[0]=='?')continue;
        else
        {
            if(d=='+')
            {
                e=atoi(c);
                if(e==a+b)n++;
            }
            else if(d=='-')
            {
                e=atoi(c);
                if(e==a-b)n++;
            }
            else continue;
        }
    }
    printf("%d",n);
    return 0;
}

C++ :

#include<iostream>
#include<cstring>
#include<cmath>
using namespace std;
int main()
{
    int f(char *);
    int a,b,r=0;
    char c1,c2,s[4];
    while(cin>>a>>c1>>b>>c2>>s)
    {
        int y;
        if(c1=='+')
            y=a+b;
        else
            y=a-b;
        if(s[0]!='?' && y==f(s))
            r++;
    }
    cout<<r<<endl;
}
int f(char *s)
{
    int i,l,y=0;
    l=strlen(s);
    for(i=l-1;i>=0;i--)
        y+=(s[i]-'0')*pow(10,l-1-i);
    return y;
}