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N Queens problem

Well, I can't possibly have an 'algorithm of the day' thread without solving the all famous N QUEENs problem.

Problem description:

Place the maximum amount of Queens on an N by N chess board and print the possible arrangements


We will be placing 1 queen at a time per row. We would start  from the left most end of the row and move 1 step to the right if there is a collision. We keep doing this till we find a spot that does poses no collisions. If there is no such spot, then one of the previous queens must be moved elsewhere.


[code language="cpp"]
//NQueen problem
using namespace std;

int N;
int Pos=0;

void NQueenDroid(int Board[100], int Remaining)
//found a solution
for(int i=0;i<N;i++) cout<<Board[i]<<" - ";

int Cur= N-Remaining; //placement of current queen
for(int i=0;i<N;i++)
bool IsColliding= false;
for(int k=0;k<Cur;k++)
//Collision in columns
if(Board[k]==i) {IsColliding=true; break;}
{IsColliding=true; break;} //Collision in diagonals
if(IsColliding) continue;
Board[Cur]=i; //place queen

int main()

cout<<"Enter the board size :";
int Board[100]={0};

//End of code
return 0;



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