[LeetCode] N-Queens

题目链接

vector<vector<string> > solveNQueens(int n) {vector<vector<string>> solutions;if (n == 0){return solutions;}int* place_queen = new int[n];for (int i = 0; i < n; i++){place_queen[i] = -1;}int index = 0;while (index >= 0){place_queen[index]++;if (place_queen[index] >= n){place_queen[index] = -1;index--;if (index < 0){break;}continue;}bool place_able = true;for (int i = 0; i < index; i++){if (place_queen[index] == place_queen[i] || place_queen[index] == (place_queen[i] + (index - i)) || place_queen[index] == (place_queen[i] - (index - i))){place_able = false;break;}}if (place_able == true){index++;if (index >= n){vector<string> solution;for (int row = 0; row < n; row++){string line;for (int col = 0; col < n; col++){if (col == place_queen[row]){line += "Q";}else{line += ".";}}solution.push_back(line);}solutions.push_back(solution);index--;place_queen[index] = -1;index--;}}}return solutions;}