////// 1+2+3+....+n的递归算法 /// /// ///public static int Process1(int i) { //计算1+2+3+4+...+100的值 if (i == 0) return 1; if (i == 1) return 1; return Process1(i - 2) + Process1(i - 1); } /// /// 1+2+3+....+n的非递归算法 /// /// ///public static int Process2(int i) { //计算1+2+3+4+...+100的值 if (i == 0) return 0; return Process2(i - 1) + i; } /// /// 1-2+3-4+5-....+n的非递归算法 /// /// /// ///public static int Process0(int isum, int itype) { int sum = 0; for (int i = 1; i <= isum; i++) { if (itype == 1) { if (i % 2 != 0) { sum += i; } else { sum += (-1) * i; } } else { sum += i; } } return sum; } /// /// 冒泡法排序 /// /// public static void order1(ref int[] arrLen) { int temp; for (int i = 0; i < arrLen.Length; i++)//冒泡法排序 for (int j = i + 1; j < arrLen.Length; j++) if (arrLen[i] > arrLen[j]) { temp = arrLen[i]; arrLen[i] = arrLen[j]; arrLen[j] = temp; } } ////// 冒泡法排序 /// /// public static void order2(ref int[] arrLen) { for (int i = 0; i < arrLen.Length - 1; i++) { for (int j = 0; j < arrLen.Length - 1 - i; j++) { if (arrLen[j] > arrLen[j + 1]) { int temp = arrLen[j]; arrLen[j] = arrLen[j + 1]; arrLen[j + 1] = temp; } } } } //折半查找、二分算法 //数组必须按照一定的顺序 //参数：最大，最小，目标（参数类型为整数） public static int BinarySearch(int min, int max, int num) { if (min == max) return -1; int mid = (min + max) / 2; if (a[mid] == num) return mid; else if (a[mid] < num) { return BinarySearch(mid + 1, max, num); } else { return BinarySearch(min, mid - 1, num); } } //折半查找、二分算法 //非递归算法 public static int BinarySearch_F(int num) { int min = 0; int max = 9; int mid; while (min <= max) { mid = (min + max) / 2; if (a[mid] == num) return mid; else if (a[mid] > num) max = mid - 1; else min = mid + 1; } return -1; } int a[10] ={1,5,10,13,17,23,65,77,81,93}