Java: sort

 

 

 

 

 

 选择排序:

  protected static void selectSort(int[] array){
    int tmp;
    int minIndex;
    for(int i = 0; i < array.length - 1; i++){
      minIndex = i;
      for(int j = i + 1; j < array.length; j++){
        if(array[j] < array[minIndex]){
          minIndex = j;
        }
      }
      if(minIndex != i){
        tmp = array[minIndex];
        array[minIndex] = array[i];
        array[i] = tmp;
      }
    }
  }

 

插入排序:

  protected static void insertSort(int[] array){
    int tmp;
    for(int i = 1; i < array.length; i++){
      tmp = array[i];
      int j = i - 1;  // 有序区最大索引
      while(j >= 0){
        if(array[j] > tmp){
          array[j + 1] = array[j];
        }else{
          // array[j + 1] = tmp;  // 不能在此处, tmp为最小值时, 不会执行
          // System.out.printf("\033[37;7m %s -- %s \033[0m\n", j + 1, tmp);
          break;
        }
        j--;
      }
      array[j + 1] = tmp;  // j + 1
      // System.out.println("\033[37;7m>>>>>> " + Arrays.toString(array) + " <<<<<<\033[0m");
    }
  }

 

单边快排

private static void quickSort(int[] array, int low, int high){
    if(low > high){  // low==high: 分区只有一个值,  low>high: pivot为分区极小值,  pivot为分区极大值: 此时右分区low为high+1, 不满足条件
      return;
    }
    int base = partition(array, low, high);
    quickSort(array, low, base - 1);  // 左分区
    quickSort(array, base + 1, high);  // 右分区

  }

  private static int partition(int[] array, int low, int high){
    int pivot = array[high];
    int base = low;
    int tmp;
    for(int cursor = base; cursor < high; cursor++){  // base左边的值小于pivot
      if(array[cursor] < pivot){
        if(cursor != base){
          tmp = array[cursor];
          array[cursor] = array[base];
          array[base] = tmp;
        }
        base++;  // base右移
      }
    }

    if(base != high && array[base] != array[high]){  // base==high, pivot为分区最大值
      tmp = array[base];
      array[base] = pivot;
      array[high] = tmp;
    }

    return base;
  }

 

 

双边快排

private static void doubleQuickSort(int[] array, int low, int high){
    // System.out.printf("\033[37;7m low: %d, high: %d \033[0m\n", low, high);
    if(low >= high)
      return;
    int partition = partition(array, low, high);
    doubleQuickSort(array, low, partition - 1);
    doubleQuickSort(array, partition + 1, high);
  }

  private static int partition(int[] array, int low, int high){
    int pivot = array[low];
    int lowCursor = low + 1;
    int highCursor = high;
    int tmp;
    while(lowCursor < highCursor){
      while(pivot < array[highCursor]){
        highCursor--;
      }
      while(lowCursor < highCursor && array[lowCursor] <= pivot){
        lowCursor++;
      }
      if(lowCursor == highCursor){
        System.out.printf("\033[37;7m Cursor: %d, lowCursor == highCursor \033[0m\n", lowCursor);
        break;
      }else{
        tmp = array[lowCursor];
        array[lowCursor] = array[highCursor];
        array[highCursor] = tmp;
      }
    }
    tmp = array[highCursor];
    array[highCursor] = pivot;
    array[low] = tmp;

    return lowCursor;
  }

 

标签：sort,tmp,Java,int,high,base,low,array
来源： https://www.cnblogs.com/dissipate/p/16343855.html