#include #include #include using namespace std; int main() { const int s = 20; int n = 20; bool full = false; int row[s][s]; srand((unsigned)time(NULL)); int q_set = 0; if( n > s ) { cout << "That won't work." << endl; } else { while(q_set < n) { q_set = 0; full = false; for(int i = 0; i < s; i++) for(int j = 0; j < s; j++) row[i][j] = 0; while(!full) { int x = rand() % s; int y = rand() % s; if(row[x][y] == 0) { for(int i = 0; i < s; i++) row[x][i] = 1; for(int i = 0; i < s; i++) row[i][y] = 1; int a = x; int b = y; while(true) { row[a][b] = 1; a++; b++; if(a >= s || b >= s) break; } a = x; b = y; while(true) { row[a][b] = 1; a++; b--; if(a >= s || b < 0) break; } a = x; b = y; while(true) { row[a][b] = 1; a--; b++; if(a < 0 || b >= s) break; } a = x; b = y; while(true) { row[a][b] = 1; a--; b--; if(a < 0 || b < 0) break; } row[x][y] = 2; q_set++; if(q_set == n) break; full = true; for(int i = 0; i < s; i++) for(int j = 0; j < s; j++) if(row[i][j] == 0) { full = false; break; } } } } } // show for(int i = 0; i < s; i++) { for(int j = 0; j < s; j++) { //*(prow + i) = 0; //cout << *(prow + i) << ' '; cout << (row[i][j] == 2 ? 'Q' : '.') << ' '; } cout << endl; } }

nine queens in C++