Recursion of a function fails - function

Question

I am working on a sudoku solver using backtracking. For some unknown by me reasons my code blocks can't use recursion. I mean that a function, even if the program reach the code line where I wrote the recursion, won't call itself. The program just continue as if nothing was there.
#include <bits/stdc++.h>
using namespace std;
ifstream in("data.in");
ofstream out("data.out");
int sudoku[10][10];
int f[10];
vector< pair<int, int> > v;
bool continuare(int pas){
int x = v[pas].first;
int y = v[pas].second;
for(int i = x; i <= 9; i++)
f[ sudoku[i][y] ]++;
for(int i = x - 1; i >= 1; i--)
f[ sudoku[i][y] ]++;
for(int j = x + 1; j <= 9; j++)
f[ sudoku[x][j] ]++;
for(int j = x - 1; j >= 1; j--)
f[ sudoku[x][j] ]++;
for( int i = x - 3 + x%3, c1 = 0; c1 < 3; c1++, i++ )
for( int j = y - 3 + y%3, c2 = 0; c2 < 3; c2++, j++ )
f[ sudoku[i][j] ]++;
for(int i = 1; i <= 9; i++){
if( f[i] > 3 )
return false;
f[i] = 0;
}
return true;
}
void afisare(){
for(int i = 1; i <= 9; i++){
for(int j = 1; j <= 9; j++)
out<<sudoku[i][j]<<" ";
out<<"\n";
}
}
void backtracking( int pas ){
if( pas > v.size() )
afisare();
else
for(int i = 1; i <= 9; i++){
sudoku[ v[pas].first ][ v[pas].second ] = i;
if( continuare(pas) )
backtracking( pas + 1 );
}
}
int main()
{
for(int i = 1; i <= 9; i++)
for(int j = 1; j <= 9; j++){
in>>sudoku[i][j];
if(sudoku[i][j] == 0)
v.push_back( make_pair(i, j) );
}
backtracking(1);
return 0;
}
As you may have noticed, the problem is when backtracking() calls itself and as I said nothing happens there.

Answer 1

Copied from comment which seemed to have solved your question:
compile with the -g flag and run your executable against gdb, I just did that and saw that it seg faults at f[ sudoku[i][j] ]++; in continuare function.