/// <summary>
/// 1+2+3+....+n的递归算法
/// </summary>
/// <param name="i"></param>
/// <returns></returns>
public static int Process1(int i)
{
if (i == 0) return 1;
if (i == 1) return 1;
return Process1(i - 2) + Process1(i - 1);
}
/// <summary>
/// 1+2+3+....+n的非递归算法
/// </summary>
/// <param name="i"></param>
/// <returns></returns>
public static int Process2(int i)
{
if (i == 0) return 0;
return Process2(i - 1) + i;
}
/// <summary>
/// 1-2+3-4+5-....+n的非递归算法
/// </summary>
/// <param name="isum"></param>
/// <param name="itype"></param>
/// <returns></returns>
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;
}
/// <summary>
/// 冒泡法排序
/// </summary>
/// <param name="arrLen"></param>
public static void order1(ref int[] arrLen)
{
int temp;
for (int i = 0; i < arrLen.Length; i++)
for (int j = i + 1; j < arrLen.Length; j++)
if (arrLen[i] > arrLen[j])
{
temp = arrLen[i];
arrLen[i] = arrLen[j];
arrLen[j] = temp;
}
}
/// <summary>
/// 冒泡法排序
/// </summary>
/// <param name="arrLen"></param>
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;
}
}
}
}
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);
}
}
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;
}<br> int a[10] ={1,5,10,13,17,23,65,77,81,93}