#include "cstdio"

int a[10],b[10];

void back(int k,int len) {
	printf("back\n");
   if(1) {
         for(int i = 1; i <= len;i++)
           printf("%d ",a[i]);
         printf("\n");
     }
	else {
         for(int  i = 1; i <= len; i++)
            if(!b[i]) {  //daca valoarea nu-i folosita  
                 a[k] = i;
                 b[i] = 1;
                 back(k+1,len); //trecem la pasul urmator
				 printf ("b[%d] = 0\n", i);
                 b[i] = 0; //o eliberam
           }
	}
}

int main() {
	freopen ("permutari.in", "r", stdin);
	freopen ("permutari.out", "w", stdout);
    int n;
    scanf("%d",&n);
    back(1,n);
    fclose(stdin); fclose(stdout);
    return 0;
}