Language: C++

#include <bits/stdc++.h>
using namespace std;

int array[2][50];

bool dfs(vector<vector<bool> >& B, int n, int s, vector<bool> & u){
    
    u[s] = 1;
    for(int i = 1; i <= n; i++){
        if(B[s][i] == 1){
            //cout << i << endl;
            B[s][i] = 0;
            B[i][s] = 0;
            dfs(B, n, i, u);
        }
    }

    for(int i = 1; i <= n; i++){
        if(u[i] == 0) return 0;
    }
    return 1;

}

int main(void)
{   
    int n, m; cin >> n >> m;
    vector<vector<bool> > A(n + 1, vector<bool>(n + 1, false));
    vector<vector<bool> > B(n + 1, vector<bool>(n + 1, false));

    for(int i = 0; i < m; i++){
        int a, b; cin >> a >> b;
        A[a][b] = true;
        A[b][a] = true;
        array[0][i] = a;
        array[1][i] = b;
    }

    int sum = 0;

    for(int i = 0; i < m; i++){

        for(int j = 1; j <= n; j++){
            for(int k = 1; k <= n; k++){
                B[j][k] = A[j][k];
            }
        }
        B[array[0][i]][array[1][i]] = 0;
        B[array[1][i]][array[0][i]] = 0;

        

        vector<bool> u(n + 1, 0);
        int s = 1;
        if(!dfs(B, n, s, u)){
            sum++;
        }

    }

    cout << sum << endl;
    return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:35:9: error: reference to 'array' is ambiguous
   35 |         array[0][i] = a;
      |         ^~~~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_pair.h:99:12: note: candidates are: 'template<class _Tp, long unsigned int _Nm> struct std::array'
   99 |     struct array;
      |            ^~~~~
a.cc:4:5: note:                 'int array [2][50]'
    4 | int array[2][50];
      |     ^~~~~
a.cc:36:9: error: reference to 'array' is ambiguous
   36 |         array[1][i] = b;
      |         ^~~~~
/usr/include/c++/14/bits/stl_pair.h:99:12: note: candidates are: 'template<class _Tp, long unsigned int _Nm> struct std::array'
   99 |     struct array;
      |            ^~~~~
a.cc:4:5: note:                 'int array [2][50]'
    4 | int array[2][50];
      |     ^~~~~
a.cc:48:11: error: reference to 'array' is ambiguous
   48 |         B[array[0][i]][array[1][i]] = 0;
      |           ^~~~~
/usr/include/c++/14/bits/stl_pair.h:99:12: note: candidates are: 'template<class _Tp, long unsigned int _Nm> struct std::array'
   99 |     struct array;
      |            ^~~~~
a.cc:4:5: note:                 'int array [2][50]'
    4 | int array[2][50];
      |     ^~~~~
a.cc:48:24: error: reference to 'array' is ambiguous
   48 |         B[array[0][i]][array[1][i]] = 0;
      |                        ^~~~~
/usr/include/c++/14/bits/stl_pair.h:99:12: note: candidates are: 'template<class _Tp, long unsigned int _Nm> struct std::array'
   99 |     struct array;
      |            ^~~~~
a.cc:4:5: note:                 'int array [2][50]'
    4 | int array[2][50];
      |     ^~~~~
a.cc:49:11: error: reference to 'array' is ambiguous
   49 |         B[array[1][i]][array[0][i]] = 0;
      |           ^~~~~
/usr/include/c++/14/bits/stl_pair.h:99:12: note: candidates are: 'template<class _Tp, long unsigned int _Nm> struct std::array'
   99 |     struct array;
      |            ^~~~~
a.cc:4:5: note:                 'int array [2][50]'
    4 | int array[2][50];
      |     ^~~~~
a.cc:49:24: error: reference to 'array' is ambiguous
   49 |         B[array[1][i]][array[0][i]] = 0;
      |                        ^~~~~
/usr/include/c++/14/bits/stl_pair.h:99:12: note: candidates are: 'template<class _Tp, long unsigned int _Nm> struct std::array'
   99 |     struct array;
      |            ^~~~~
a.cc:4:5: note:                 'int array [2][50]'
    4 | int array[2][50];
      |     ^~~~~