Hard NQUEENS problem

#1

I am passing only 2 cases
i have implemented recursion and backtracking as suggested in video
why all cases are not passed

#2

Hi Anand , Can you share your code

#3

//SUDOKU SOLVER using Recursion and BackTracking #include <bits/stdc++.h> using namespace std; //for checking whether queen can be placed at (i,j) pos bool checkplaced(int mat[15][15],int i,int j,int n){ //checking row and column int x,y; for(x=0;x<i;x++){ if(mat[x][j]==1)return false; } //checking diagonal for(x=i,y=j;x>=0&&y>=0;x–,y–){ if(mat[x][y]==1)return false; } for(x=i,y=j;x>=0&&y<n;x–,y++){ if(mat[x][y]==1)return false; } return true; } int nqueens(int mat[15][15],int i,int n){ //base case static int count=0; if(i==n){ count=count+1; // for(int i=0;i<n;i++){for(int j=0;j<n;j++){ // cout<<mat[i][j]<<" "; // }cout<<endl;} //cout<<count<<endl; return count; } //recursion for (int x=0;x<n;x++){ bool check=checkplaced(mat,i,x,n); if(check){ mat[i][x]=1; nqueens(mat,i+1,n); mat[i][x]=0; } } return count; } int main() { int n; cin>>n; int mat[15][15]; memset(mat,0,sizeof mat); int res=nqueens(mat,0,n); cout<<res<<endl; }

#4

hi Anand ,can you share your code using https://ide.codingblocks.com/ so that it would be easier for me to understand

#5

doubt resolved on chat !!

#6

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