/* This code will take input for 10 integers given by the user
into an array, sort them with a recursive merge function
and print the updated array in ascending order. */

#include <stdio.h>
#define ARRSIZE 10

void merge_sort (int arr[], int temp[], int left, int right);
void merge (int arr[], int temp[], int left, int mid, int right);

int main (void){
    int arr[ARRSIZE], temp[ARRSIZE], left, right, i;

    arr[0] = 3;
    arr[1] = 5;
    arr[2] = 7;
    arr[3] = 6;
    arr[4] = 8;
    arr[5] = 9;
    arr[6] = 10;
    arr[7] = 2;
    arr[8] = 1;
    arr[9] = 4;
    left = 0;
    right = ARRSIZE-1;

    merge_sort(arr, temp, left, right);

    printf("\nHere is your updated array:");
    printf("\n{");
    for(i=0;i<ARRSIZE;i++){
        printf("%d,", arr[i]);
    }
    printf("}");

    return 0;
}

void merge_sort (int arr[], int temp[], int left, int right){
    if(left<right){
        int mid = (right+left)/2;
        merge_sort(arr, temp, left, mid);
        merge_sort(arr, temp, mid+1, right);
        merge(arr, temp, left, mid, right);
    }
}

void merge (int arr[], int temp[], int left, int mid, int right){
    int i, j, tempi = left;
    for (i = left, j = 1 + mid; i <= mid && j <= right; ++tempi)
    {
      if (arr[i] < arr[j]) temp[tempi] = arr[i++];
      else                  temp[tempi] = arr[j++];
    }
    if (i > mid) right = tempi - 1;
    for (; tempi <= right; ++tempi, ++i) temp[tempi] = arr[i];
    for(i=left; i<=right; ++i){
        arr[i] = temp[i];
    }
}