#include <stdio.h>
 
void swap(char *x, char *y){
    char w;
    w = *x;
    *x = *y;
    *y = w;
}
 
void permute(char *str, int start, int n, int minLength, int maxLength)
{
    int i;
 
    if (start >= minLength)
    {
        char temp = str[start]; // store the character, so we don't lose it
        str[start] = 0; // 0x00 - end of string
        printf("%s\n", str);
        str[start] = temp;
    }
 
    if (start == maxLength)
        return;
 
    for (i = start; i < n; i++)
    {
        swap(str+i, str+start);
        permute(str, start+1, n, minLength, maxLength);
        swap(str+i, str+start);
    }
}
 
int main(void) {
	char arr[] = "abcde ";
	permute(arr, 0, 5, 2, 4);
	return 0;
}
 

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