Segmentation fault

[wise narwhal]

I am writing a program to find all unique paths from 0,0 to the bottom right corner of a matrix, while only moving on open spaces (0) and not obstacles(1)
I used recursion to check each path, allowing the program to go up, down, right, left.
Every time I run the program, there is segmentation fault. Can someone help me figure out why? I can't find the solution after a long time.

#include<bits/stdc++.h>
using namespace std;
 
int  UniquePathHelper(int i, int j, int r, int c, vector<vector<int>>& A){
    // boundary condition or constraints
    if(i == r || j == c || i < 0 || j < 0){
      return 0 ;
    }
 
    if(A[i][j] == 1){
      return 0 ;
    }
     
    // base case
    if(i == r-1 && j == c-1){
      return 1 ;
    }
 
    return  UniquePathHelper(i+1, j, r, c, A) +
            UniquePathHelper(i, j+1, r, c, A) + 
            UniquePathHelper(i-1, j, r, c, A) +
            UniquePathHelper(i, j-1, r, c, A) ;
}
 
 
int uniquePathsWithObstacles(vector<vector<int>>& A)
{
     
    int r = A.size(), c = A[0].size();
 
     
    return UniquePathHelper(0, 0, r, c, A) ;
}
 
// Driver code
int main()
{
   vector<vector<int>> A = { { 0, 0, 0 },
                             { 0, 1, 0 },
                             { 0, 0, 0 } };
                              
   cout << uniquePathsWithObstacles(A) << " \n";                                               
}```

[empty patio]

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[wise narwhal]

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[late pike]

#include <vector>
#include <iostream>

int UniquePathHelper(int i, int j, int r, int c, std::vector<std::vector<int>>& A) {
  // boundary condition or constraints
  if (i >= r || j >= c || i < 0 || j < 0) {
    return 0;
  }

  if (A[i][j] == 1) {
    return 0;
  }

  // base case
  if (i == r - 1 && j == c - 1) {
    return 1;
  }

  A[i][j] = 1;

  return UniquePathHelper(i + 1, j, r, c, A) + UniquePathHelper(i, j + 1, r, c, A) + UniquePathHelper(i - 1, j, r, c, A) + UniquePathHelper(i, j - 1, r, c, A);
}

int uniquePathsWithObstacles(std::vector<std::vector<int>>& A) {
  int r = A.size(), c = A[0].size();

  return UniquePathHelper(0, 0, r, c, A);
}

// Driver code
int main() {
  std::vector<std::vector<int>> A = {{0, 0, 0}, {0, 1, 0}, {0, 0, 0}};

  std::cout << uniquePathsWithObstacles(A) << std::endl;
}

[late pike]

;compile cpp

[kind blaze]

Program Output

2

Haxxolotl#1269 | 47ms | c++ | x86-64 gcc 12.2 | godbolt.org

[late pike]

you are forgetting to set visited squares as visited, it will run forever

and maybe use >= for the upper bounds just in case instead of ==

[wise narwhal]

oh yeah

let me try ur code gimme a sec

ok it works

i totally forgot the visited

thank you

!solved