44 ba c

#include <iostream>
#include <fstream>
#include <cstring>
#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
using namespace std;

ifstream fin("A.txt");

int main()
{
    unsigned k = 0;
    char s[31];
    while (fin.getline(s, 31))
    {
        char *p = strtok(s, "+=");
        int nr1 = atoi(p);
        p = strtok(NULL, "+=");
        int nr2 = atoi(p);
        p = strtok(NULL, "+=");
        int res = atoi(p);
        if (nr1 + nr2 == res)
            k++;
    }

    cout << k;
    return 0;
}