/*=============================================================================##   FileName:  mergeSort.c#   Algorithm: 歸并排序（自底向上）#   Author:   Knife#   Created:  2014-06-14 16:40:02#=============================================================================*/#include<stdio.h>#include<stdlib.h>void merge_sort(int* intArr, int intArr_len);void merge_array(int* intArr1, int len1, int* intArr2, int len2);void main(){  int intArr[] = {8,3,6,4,2,9,5,4,1,7};  int n = sizeof (intArr) / sizeof (intArr[0]);  int i = 0;  merge_sort(intArr, n);  for(;i<n;i++){    printf("%d ",intArr[i]);  }  printf("/n");}//歸并排序（自底向上）void merge_sort(int* intArr, int intArr_len){  int len = 1;  int k = 0;  while (len < intArr_len) {     int i = 0;     for (; i + 2*len <= intArr_len; i += 2*len){      int* intArr1 = intArr + i;      int intArr1_len = len;      int* intArr2 = intArr + i + len;      int intArr2_len = len;      merge_array(intArr1, intArr1_len, intArr2, intArr2_len);     }    if (i + len <= intArr_len){       int* intArr1 = intArr + i;      int intArr1_len = len;      int* intArr2 = intArr + i + len;      int intArr2_len = intArr_len - i - len;      merge_array( intArr1, intArr1_len, intArr2, intArr2_len);     }    len *= 2;  //有序子序列長度*2   } }//合并兩個數組，并排序void merge_array(int* intArr1, int len1, int* intArr2, int len2){  //申請分配空間  int* list = (int*) malloc((len1+len2) * sizeof (int));  int i = 0, j = 0, k = 0;  while(i < len1 && j < len2){     // 把較小的那個數據放到結果數組里， 同時移動指針    list[k++] = (intArr1[i] < intArr2[j]) ? intArr1[i++] : intArr2[j++];  }  // 如果 intArr1 還有元素，把剩下的數據直接放到結果數組  while(i < len1){    list[k++] = intArr1[i++];  }  // 如果 intArr2 還有元素，把剩下的數據直接放到結果數組  while(j < len2){    list[k++] = intArr2[j++];  }   // 把結果數組 copy 到 intArr1 里  for(i = 0; i < k; i++){    intArr1[i] = list[i];  }  //釋放申請的空間  free(list);}