3、 /** * 得到数组元素位次 * @param a */ public static void GetPos(int a[], int val) { int pos = a.length; for(int i = 0; i < a.length; i++) { if(val == a[i]) { pos = i; break; } } if(a.length == pos) { System.out.println("not found"); } else { System.out.println(partation(a, pos, 0, a.length - 1)); } } /** * 分块 * @param a * @param pos * @param low * @param high * @return */ public static int partation(int a[], int pos, int low, int high) { int temp = a[pos]; while(low < high) { while(low < high && temp <= a[high]) { high--; } a[pos] = a[high]; a[high] = temp; while(low < high && temp >= a[low]) { low++; } a[high] = a[low]; a[low] = temp; } return a.length - low; }