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Copy pathNQueue.cpp
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89 lines (64 loc) · 1.68 KB
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#include <iostream>
#include <vector>
using namespace std;
void printBoard(const vector<vector<int>>& board) {
int N = board.size();
for (int i = 0; i < N; i++) {
for (int j = 0; j < N; j++) {
if (board[i][j] == 1) {
cout << "Q ";
} else {
cout << ". ";
}
}
cout << endl;
}
}
bool isSafe(const vector<vector<int>>& board, int row, int col) {
int N = board.size();
for (int i = 0; i < col; i++) {
if (board[row][i] == 1) {
return false;
}
}
for (int i = row, j = col; i >= 0 && j >= 0; i--, j--) {
if (board[i][j] == 1) {
return false;
}
}
for (int i = row, j = col; i < N && j >= 0; i++, j--) {
if (board[i][j] == 1) {
return false;
}
}
return true;
}
bool solveNQueens(vector<vector<int>>& board, int col) {
int N = board.size();
if (col >= N) {
return true;
}
for (int i = 0; i < N; i++) {
if (isSafe(board, i, col)) {
board[i][col] = 1;
if (solveNQueens(board, col + 1)) {
return true;
}
board[i][col] = 0;
}
}
return false;
}
int main() {
int N;
cout << "Enter the value of N for the N-Queens problem: ";
cin >> N;
vector<vector<int>> board(N, vector<int>(N, 0));
if (solveNQueens(board, 0)) {
cout << "Solution for " << N << "-Queens problem:" << endl;
printBoard(board);
} else {
cout << "No solution exists for the " << N << "-Queens problem." << endl;
}
return 0;
}