void nqueens(int n, int j, char *a, int *solutions, int depth)
{
int i;
int *csols;
if (n == j) {
/* good solution, count it */
*solutions = 1;
mycount++;
return;
}
*solutions = 0;
csols = alloca(n*sizeof(int));
memset(csols,0,n*sizeof(int));
/* try each possible position for queen <j> */
for (i = 0; i < n; i++) {
#pragma omp task untied
{
/* allocate a temporary array and copy <a> into it */
char * b = alloca((j + 1) * sizeof(char));
memcpy(b, a, j * sizeof(char));
b[j] = i;
if (ok(j + 1, b))
nqueens(n, j + 1, b,&csols[i],depth);
}
}
#pragma omp taskwait
for ( i = 0; i < n; i++) *solutions += csols[i];
}
void find_queens (int size)
{
total_count=0;
printf("%d-Queens: ", size);
#pragma omp parallel
{
#pragma omp single
{
char *a;
a = alloca(size * sizeof(char));
#ifdef _OPENMP
double start = omp_get_wtime();;
#else
clock_t start = clock();
#endif
nqueens(size, 0, a, &total_count,0);
//printf("completed!\n");
#ifdef _OPENMP
double time = omp_get_wtime() - start;
printf("%f sec\n", time);
#else
double end = clock();
float time = (float)(end-start) / CLOCKS_PER_SEC;
printf("%f sec\n", time);
#endif
}
#pragma omp atomic
total_count += mycount;
}
}
void nqueens(char *config, int n, int i)
{
char *new_config;
int j;
if (i==n)
{
count++;
}
/* try each possible position for queen <i> */
for (j=0; j<n; j++)
{
/* allocate a temporary array and copy the config into it */
new_config = malloc((i+1)*sizeof(char));
memcpy(new_config, config, i*sizeof(char));
if (safe(new_config, i, j))
{
new_config[i] = j;
nqueens(new_config, n, i+1);
}
free(new_config);
}
// sync
return;
}
int main(int argc, char **argv) {
#ifdef WOOL
argc = wool_init(argc, argv);
#endif
if(argc < 2) {
#ifdef WOOL
fprintf(stderr, "Usage: nqueens <woolopt> <n>\n");
#else
fprintf(stderr, "Usage: nqueens <n>\n");
#endif
return 1;
}
int n = atoi(argv[1]);
char *a = (char *) malloc(n * sizeof(char));
#ifdef WOOL
printf("nqueens(%dx%d) = %d\n", n, n, CALL(nqueens, n, 0, a));
wool_fini();
#else
printf("nqueens(%dx%d) = %d\n", n, n, nqueens(n, 0, a));
#endif
return 0;
}
int main()
{
int i;
for (i = 1; i <= 8; i++)
nqueens(i);
return 0;
}
int totalNQueens(int n) {
res = 0;
int *A = new int[n];
nqueens(A, 0, n);
delete A;
return res;
}
int main(int argc, char *argv[]) {
int n = 13;
char *a;
int res;
if (argc < 2) {
fprintf (stderr, "Usage: %s [<cilk-options>] <n>\n", argv[0]);
fprintf (stderr, "Use default board size, n = 13.\n");
} else {
n = atoi (argv[1]);
printf ("Running %s with n = %d.\n", argv[0], n);
}
a = (char *) alloca (n * sizeof (char));
res = 0;
res = nqueens(n, 0, a);
if (res == 0) {
printf ("No solution found.\n");
} else {
printf ("Total number of solutions : %d\n", res);
}
return 0;
}
void nqueens(int i, char **currentBoard, int currentProfit, int numQ, int maxProfit[], int maxProfIndex) {
register int j;
int n = gm->n;
char ** maxBoard = gm->maxBoard;
if (i < n) {
for (j = 0; j < n; j++) {
if (canPlace(i, j, currentBoard)) {
// Creating a new board
register int x,y;
char **newBoard;
newBoard = (char**)G_MALLOC(n*sizeof(char*));
for (x = 0; x < n; x++) {
newBoard[x] = (char*)G_MALLOC(n*sizeof(char*));
for (y = 0; y < n; y++) newBoard[x][y] = currentBoard[x][y];
}
newBoard[i][j] = 1;
int profitAdd = abs(i - j);
nqueens(i + 1, newBoard, currentProfit + profitAdd, numQ + 1, maxProfit, maxProfIndex);
}
}
}
else {
gm->total = gm->total + 1;
if (currentProfit > maxProfit[maxProfIndex]) {
maxProfit[maxProfIndex] = currentProfit;
gm->global_max_profit = currentProfit;
for (i = 0; i < n; i++)
for (j = 0; j < n; j++)
gm->maxBoard[i][j] = currentBoard[i][j];
}
}
}
void nqueens(int n, int j, char *a, int *solutions, int depth)
{
int *csols;
int i;
if (n == j) {
/* good solution, count it */
*solutions = 1;
return;
}
*solutions = 0;
csols = (int *)malloc(n*sizeof(int));
memset(csols,0,n*sizeof(int));
/* try each possible position for queen <j> */
for (i = 0; i < n; i++) {
#pragma omp task untied firstprivate(n, csols, i, j, a, depth, solutions)
{
/* allocate a temporary array and copy <a> into it */
char * b = (char *)malloc(n * sizeof(char));
memcpy(b, a, j * sizeof(char));
b[j] = (char) i;
if (ok(j + 1, b))
nqueens(n, j + 1, b,&csols[i],depth); //FIXME: depth or depth+1 ???
}
}
#pragma omp taskwait
for ( i = 0; i < n; i++) *solutions += csols[i];
free(csols);
}
vector<vector<string> > solveNQueens(int n)
{
res.clear();
vector<int> A(n, -1);
nqueens(A, 0, n);
return res;
}
int Ex51::totalNQueens(int n)
{
int res=0;
int *A = new int[n];
nqueens(A, 0, n, res);
delete A;
return res;
}
/* Main Function */
int main()
{
int n;
printf("\n Entrer Le nombre de reines: ");
scanf("%d",&n);
nqueens(n);
getch();
}
int main()
{
queens_bruteforce();
nqueens(N);
printf("\nPress any key to continue...");
getchar();
return(0);
}
int main()
{
int k=1,n;
printf("Enter the number n for n X n chessboard\n");
scanf("%d",&n);
nqueens(k,n);
return 0;
}
int main(void)
{
int param;
while (1) {
scanf("%d", ¶m);
printf("%d\n", nqueens(param));
}
return 0;
}
static gpointer nqueens_for(unsigned int start, unsigned int end, void *data, gint thread_number)
{
unsigned int i;
for (i = start; i <= end; i++) {
nqueens(0);
}
return NULL;
}
void find_queens (int size)
{
char *a;
total_count=0;
a = alloca(size * sizeof(char));
bots_message("Computing N-Queens algorithm (n=%d) ", size);
nqueens(size, 0, a, &total_count);
bots_message(" completed!\n");
}
void Ex51::nqueens(int A[], int cur, int n, int &res)
{
if (cur == n) { res++; return; }
else
for (int i = 0; i < n; i++)
{
A[cur] = i;
if (isValid(A, cur)) nqueens(A, cur+1, n, res);
}
}
int main()
{
printf("Enter the value of n:");
scanf("%d",&n);
int i,j;
for(i=0;i<n;i++)
for(j=0;j<n;j++)
a[i][j]='.';
nqueens(0);
return 0;
}
void nqueens(vector<int> A, int cur, int n)
{
if (cur == n)
printres(A, n);
else
{
for (int i = 0; i < n; i++)
{
A[cur] = i;
if (isValid(A, cur))
nqueens(A, cur + 1, n);
}
}
}
/* Main Function */
int main()
{
int n;
printf("----------------------------------------------------\n");
printf("-------------Made by C codechamp--------------------\n");
printf("----------------------------------------------------\n\n");
printf("\t C PROGRAM OF N-QUEEN PROBLEM\n\n");
printf("\nEnter the no. of Queens : ");
scanf("%d",&n);
printf("\n\n\tUSING %d QUEEN'S STRATEGY \n\n",n);
nqueens(n);
system("pause");
getch();
}
void nqueens(int A[], int cur, int n){
if (cur == n){
++res;
return;
}
else{
for (int i = 0; i < n; ++i){
A[cur] = i;
if(isValid(A, cur)){
nqueens(A, cur + 1, n);
}
}
}
}
static void main_entrypoint(void *____arg) {
main_entrypoint_ctx *ctx = (main_entrypoint_ctx *)____arg;
int size; size = ctx->size;
{
total_count=0;
bots_message("Computing N-Queens algorithm (n=%d) ", size);
hclib_start_finish(); {
char *a;
a = (char *)malloc(size * sizeof(char));
nqueens(size, 0, a, &total_count,0);
} ; hclib_end_finish();
bots_message(" completed!\n");
} ; free(____arg);
}
int nqueens(int y)
{
int x;
for (x = 0; x < QUEENS; x++) {
if (safe((row[y - 1] = x), y - 1)) {
if (y < QUEENS) {
nqueens(y + 1);
} else {
break;
}
}
}
return 0;
}
TASK_3(int, nqueens, int, n , int, j, char*, a) {
#else
int nqueens(int n, int j, char *a) {
#endif
// No more queens to place.
if(n == j) {
return 1;
}
// Try each possible position for queen <j>
int solutions = 0;
for(int i = 0; i < n; i++) {
#ifdef WOOL
SPAWN(nqueens_next, n, j, a, i);
#else
a[j] = i;
if(ok(j + 1, a)) {
solutions += nqueens(n, j + 1, a);
}
#endif
}
#ifdef WOOL
for(int i = 0; i < n; i++) {
solutions += SYNC(nqueens_next);
}
#endif
return solutions;
}
#ifdef WOOL
TASK_IMPL_4(int, nqueens_next, int, n, int, j, char*, a, int, i) {
char *b = (char *) alloca((j + 1) * sizeof(char));
memcpy(b, a, j * sizeof(char));
b[j] = i;
if(ok(j + 1, b)) {
return CALL(nqueens, n, j + 1, b);
} else {
return 0;
}
}
void find_queens (int size)
{
{
total_count=0;
bots_message("Computing N-Queens algorithm (n=%d) ", size);
{
{
char *a;
a = (char *)malloc(size * sizeof(char));
nqueens(size, 0, a, &total_count,0);
}
}
bots_message(" completed!\n");
}
}
int main(int argc, char *argv[])
{
int num_queens, *positions, count;
if(argc != 2)
{ printf("Usage: %s <number of queens (chess board order)>\n", argv[0]);
exit(1);
}
num_queens = atoi(argv[1]);
initscr();
cbreak();
keypad(stdscr, TRUE);
positions = nqueens(num_queens);
free(positions);
endwin();
return 0;
}
void nqueens(int k,int n)
{
int i;
for(i=1;i<=n;i++)
{
if(place(k,i))
{
x[k]=i;
if(k==n)
{
printf("The solution is\n");
print(n);
}
else
nqueens(k+1,n);
}
}
}
void nqueens_wrapper(void){
int i, j, n, p, pid;
char **initialBoard;
initialBoard = gm->initialBoard;
int maxProfit[1];
maxProfit[0] = 0;
n = gm->n;
p = gm->p;
GET_PID(pid);
for (i = pid; i < n; i += p) {
// initialBoard[0][i] = 1;
nqueens(0, initialBoard, 0, 0, maxProfit, 0);
// initialBoard[0][i] = 0;
}
}
int get_result(size_t size,size_t points_size,point_t *points,unsigned int ***result)
{
size_t iter = 0,iter_ = 0;
*result = nqueens(size);
if(!*result){
return 0;
}
while((*result)[iter]){
if(result_filter(size,points_size,points,(*result)[iter])){
(*result)[iter_] = (*result)[iter];
iter_++;
}
else{
free((*result)[iter]);
}
iter++;
}
(*result)[iter_] = NULL;
return 1;
}
