归并排序

#include<stdlib.h>
#include<stdio.h>
 
void Merge(int sourceArr[],int tempArr[],int startIndex,int midIndex,int endIndex)
{
    int i = startIndex,j=midIndex+1,k = startIndex;
    while(i!=midIndex+1 && j!=endIndex+1)
    {
        if(sourceArr[i]>sourceArr[j])
            tempArr[k++] = sourceArr[i++];
        else
            tempArr[k++] = sourceArr[j++];
    }
    while(i!=midIndex+1)
        tempArr[k++] = sourceArr[i++];
    while(j!=endIndex+1)
        tempArr[k++] = sourceArr[j++];
    for(i=startIndex;i<=endIndex;i++)
        sourceArr[i] = tempArr[i];
}
 
//内部使用递归
void MergeSort(int sourceArr[],int tempArr[],int startIndex,int endIndex)
{
    int midIndex;
    if(startIndex<endIndex)
    {
        midIndex=(startIndex+endIndex)/2;
        MergeSort(sourceArr,tempArr,startIndex,midIndex);
        MergeSort(sourceArr,tempArr,midIndex+1,endIndex);
        Merge(sourceArr,tempArr,startIndex,midIndex,endIndex);
    }
}
 
int main(int argc,char * argv[])
{
    int a[8]={50,10,20,30,70,40,80,60};
    int i,b[8];
    MergeSort(a,b,0,7);
    for(i=0;i<8;i++)
        printf("%d ",a[i]);
    printf("\n");
    return 0;
}