#include <stdio.h>  
#include <string.h> 
#include <malloc.h> 
 
void print(int *num, int n) 
{   
 int i; 
 for ( i = 0 ; i < n ; i++) 
    printf("%d ", num[i]);  
   printf("\n");    
}   
 
int*permute(int*i,int h)    
{       
     int temp = *i; 
    *i = *(i+h);    
    *(i+h) = temp;  
return i+1; 
 
}   
void recursive_permute(int*i,int *j,int n)  
{   
    if((j-i)==n-1) {print(i,n);return;};
 
    int *tmparray=(int*)malloc(n*sizeof(int));
    memcpy(tmparray,i,n*sizeof(int));
    recursive_permute(tmparray,tmparray+(j-i+1),n);
 
    for (int h=1;h<n-(j-i);h++) recursive_permute(tmparray,permute(tmparray+(j-i),h),n);
}   
 
int main()  
{   
 int num[100];  
 int *ptr;  
 int temp;  
 int i, n, j;   
 printf("\nHow many number you want to enter: ");   
    scanf("%d", &n);    
 printf("\nEnter a list of numbers to see all combinations:\n");    
 for (i = 0 ; i < n; i++)   
    scanf("%d", &num[i]);   
 printf("my recursive method ---------------------------\n");   
 recursive_permute(num,num,n);  
 
 printf("your method -----------------------------------\n");   
 
 for (j = 1; j <= n; j++) { 
    for (i = 0; i < n-1; i++) { 
        temp = num[i];  
        num[i] = num[i+1];  
        num[i+1] = temp;    
        print(num, n);  
 }  
}   
 return 0;  
}  

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