Incorrect Soln

ACSoln.cpp

#define ll long long 
#define fr(v,s,n) for(int v=s;((s<n)?v<n:v>n);((s<n)?v++:v--))
#define debug(p) cout<<#p<<' '<<p<<'\n';
#define debuga(a,i) cout<<#a<<"["<<i<<"]"<<" "<<a[i]<<"\n";
#define debugal(a) for(int v=0;v<(sizeof(a)/sizeof(a[0]));v++) cout<<#a<<"["<<v<<"]"<<" "<<a[v]<<"\n";
#define debugm(a,i,j) cout<<#a<<"["<<i<<"]["<<j<<"]"<<" "<<a[i][j]<<"\n";
#define pb push_back
#define mp make_pair
#define vii vector<pair<int,int>>
#define vi vector<int>
#define si stack<int>
#define fread(ff) freopen(ff,"r",stdin);
#define fwrite(ff) freopen(ff,"w",stdout);
#define dbl double
#define fio ios_base::sync_with_stdio(false); cin.tie(NULL);
#define sec second
#define fst first
#define sep cout<<"\n------------------\n";


int Solution::solve(vector<vector<int> > &A, int B) {
    int n = A.size();
    int m = A[0].size();
    
    vector<int> c;
    fr(i,0,n) fr(j,0,m) c.pb(A[i][j]);
    
    vector<int>mm(c.size());
    //
    //
    // mod fn not corrected
    //
    // i am not taking care of c[i] being negative or positive here
    // it gives AC
    //
    //
    fr(i,0,n*m) mm[i] = c[i]%B;
    
    sort(mm.begin(),mm.end());
    if(mm[0] != mm[n*m -1]) return -1;
    
    
    sort(c.begin(),c.end());
    
    int index = (int)((m*n)/2);
    int median = c[index];
    // debug(median)
    
    int ans = 0;
    fr(i,0,m*n)
    {
        // sep
        
        int tt = abs(c[i] - median);
        int temp = (tt/B);
        // debug(tt)
        // debug(temp)debug(c[i])
        ans += temp;
        // debug(ans);
        // sep
    }
    
    return ans;
}