BOISO C++

#include <bits/stdc++.h>
using namespace std;
string s;
int check(char c1,char c2,char c3)
{
    int a,b,c;
   if(c1=='0') return 0;
   a=int(c1)-48;
   b=int(c2)-48;
   c=int(c3)-48;
   if(a+c==b) return 1;
   else return 0;
}

void giai()
{
   int res=0;
   for(int i=0;i<=s.length()-3;i++)
        res=res+check(s[i],s[i+1],s[i+2]);
   cout<<res;
}

int main()
{
   // freopen("boiso.inp","r",stdin);
   // freopen("boiso.out","w",stdout);
    cin>>s;
    giai();
}