#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[j++];
else
tempArr[k++] = sourceArr[i++];
}
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];
}
//內部使用遞歸
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;
}