Merge sort-recursive algorithm and non-recursive

Recursive dynamic graph:

Recursive code:

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#define N 100000+100

int map[N];
int temp[N];
long long int sum;
void marge(int l, int ld, int r, int rd)
{
    int p = 0;
    int i = l;
    int j = r;
    while(i<=ld && j<=rd)
    {
        if(map[i]<=map[j])
        {
            temp[p++] = map[i++];
        }
        else
        {
            temp[p++] = map[j++];
            sum = sum + (ld-i+1);
        }
    }
    while(i<=ld)
    {
        temp[p++] = map[i++];
    }
    while(j<=rd)
    {
        temp[p++] = map[j++];
    }
    int k;
    for(k=l; k<=rd; k++)
    {
        map[k] = temp[k-l];
    }
}

void msort(int l ,int r)
{
    int mid;
    if(l<r)
    {   mid = (l+r)/2;
        msort(l, mid);
        msort(mid+1, r);
        marge(l, mid, mid+1, r);
    }
}

int main()
{
    int n, i;
    scanf("%d", &n);
    sum = 0;
    for(i=0; i<n; i++)
    {
        scanf("%d", &map[i]);
    }
    msort(0, n-1);
    for(i=0; i<n; i++)
    {        if(i==n-1)
           printf("%d\n", map[i]);
       else
           printf("%d ", map[i]);
    }
    printf("%lld\n", sum);
    return 0;
}

 

Non-recursive:

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Origin blog.csdn.net/weixin_42137874/article/details/81805889