infinite loop - Language C - QuickSort -

i trying code quick sort program in c, , recursive function in infinite loop.

the problem is:

you have been given array of size n.this array contains integers ranging 1 10^9. need sort contents of array value , print contents of it.

input format:

the first line contains single integers n denoting size of array. next line contains n space separated integers denoting contents of array.

output format:

print n space separated integers, i.e. final sorted array.

constraints:

1≤n≤10^6

1≤a[i]≤10^9

void fill_vet(unsigned int a[], unsigned int n){     int i;     for(i=0; i<n; i++)         scanf("%u", &a[i]); }  void print_vet(unsigned int a[], unsigned int n){     int i;     for(i=0; i<n; i++)         printf("%u ", a[i]); }  int partition(unsigned int a[], int start, int end){     int i, j;     unsigned int pivot, n_swap;     = start + 1;     pivot = a[start];     for(j = start+1; j<=end; j++){         if(a[j] < pivot){             n_swap = a[j];             a[j] = a[i];             a[i] = n_swap;             i++;         }     }      n_swap = a[i-1];     a[i-1] = a[start];     a[start] = n_swap;     return i-1; }  void sort_array(unsigned int a[], int start, int end){     while(start < end){         int pos_piv = partition(a, start, end);         sort_array(a, start, pos_piv-1);         sort_array(a, pos_piv+1, end);     } }  int main() {     unsigned int n, a[100000];     scanf("%u", &n);     fill_vet(a, n);     sort_array(a, 0, n-1);     print_vet(a, n);     return 0; } 

can tell me error pls!

you using recursion don't need loop:

void sort_array(unsigned int a[], int start, int end){   if(start < end){     int pos_piv = partition(a, start, end);     sort_array(a, start, pos_piv-1);     sort_array(a, pos_piv+1, end);   } }