C语言学习Day21

今天主要学习了数组的算法：

#include<stdio.h>
#include<stdlib.h>
#include<time.h>

//求斐波拉兹数列
void Fibonacci()
{
	int arr[20] = { 1, 1 };

	for (int i = 2; i < 20; i++)
	{
		arr[i] = arr[i - 1] + arr[i - 2];
	}
	for (int i = 0; i < 20; i++)
	{
		if (0 == i % 5)
		{
			printf("\n");
		}
		printf("%d\t", arr[i]);

	}
	printf("\n");
}

//冒泡排序
void MaoPao()
{
	int arr[10];
	//随机数种子
	srand((unsigned)time(NULL));

	//随机输入
	for (int i = 0; i < 10; i++)
	{
		//随机分配10个数到数组中
		arr[i] = rand() % 100;
	}

	//排序
	int mark = 10, flag = 0;	
	for (int i = 0; i < --mark;)
	{
		int x = 0;
		for (int j = 0; j < mark; j++)
		{
			if (arr[j] > arr[j+1])
			{
				int temp = arr[j];
				arr[j] = arr[j+1];
				arr[j+1] = temp;
			}
			x++;

		}
		printf("%d\t", x);
		flag++;
	}

	printf("%d\n", flag);
	//输出
	for (int i = 0; i < 10; i++)
	{
		if (0 == i % 5)
		{
			printf("\n");
		}
		printf("%d\t", arr[i]);
	}
	printf("\n");
}

//二维数组行列互换函数
void TwoArray1()
{
	int arr1[2][3] = { {1,2,3},{4,5,6} };
	int arr2[3][2] = { 0 };

	//二维数组行
	for (int i = 0; i < 2; i++) {
		//二位数组列
		for (int j = 0; j < 3; j++) {
			arr2[j][i] = arr1[i][j];
		}
	}
	
	//输出二维数组
	for (int i = 0; i < 3; i++) {
		for (int j = 0; j < 2; j++) {
			printf("%d\t", arr2[i][j]);
		}
		printf("\n");
	}

}

//找出二维数组中最大的那个数和他的行列
void TwoArray2()
{
	int arr[3][4] = {0};

	//随机赋值
	srand((unsigned)time(NULL));
	for (int i = 0; i < 3; i++) {
		for (int j = 0; j < 4; j++) {
			arr[i][j] = rand() % 100;
		}
	}

	//求最大值
	int max = arr[0][0],row,col;
	for (int i = 0; i < 3; i++) {
		for (int j = 0; j < 4; j++) {
			if (arr[i][j] > max) {
				max = arr[i][j];
				row = i + 1;//用于保存最大值行
				col = j + 1;//用于保存最大值列
			}
		}
	}

	//输出二维数组
	for (int i = 0; i < 3; i++) {
		for (int j = 0; j < 2; j++) {
			printf("%d\t", arr[i][j]);
		}
		printf("\n");
	}
	printf("最大值为：>%d\n其坐标为：>(%d,%d)", max, row, col);

}

//输出某一行和某一列，其余位置空白
void TwoArray3()
{
	int arr[3][3] = { {1,2,3},{4,5,6},{7,8,9} };
	for (int i = 0; i < 3; i++) {
		for (int j = 0; j < 3; j++) {
			if (i == 1 || j == 1) {
				printf("%-5d", arr[i][j]);
			}
			else {
				printf("%-5c",' ');
			}
		}
		printf("\n");
	}
}

//二分法查找
void Half()
{
	int arr[10] = { 1,2,3,76,345,887,34,67 };
	int left = 0, right = 9, mid;
	////随机赋值
	//srand((unsigned)time(NULL));
	//for (int i = 0; i < 10; i++) 
	//{
	//	arr[i] = rand() % 100;
	//}

	//用插入排序
	for (int i = 1; i < 10; i++)
	{
		int key = arr[i];
		int j = i - 1;
		while ((j >= 0) && (arr[j] > key))
		{
			arr[j + 1] = arr[j];
			j--;
		}
		arr[j + 1] = key;
	}

	for (int i = 0; i < 10; i++)
	{
		printf("%d\t", arr[i]);
	}
	printf("\n");

	//折半查找

	while (left < right)
	{
		mid = (left + right) / 2;
		if (3 == arr[mid])
		{
			printf("3的位置为：>%d\n", mid);
			break;
		}
		else if (3 > arr[mid])
		{
			right = mid;
		}
		else
		{
			left = mid;
		}
	}
}

int main()
{
#if(0)
	Fibonacci();//调用斐波拉兹函数
	MaoPao();//调用冒泡排序
	TwoArray1();//调用二维数组行列互换函数
	TwoArray2();//找出二维数组中最大的那个数和他的行列
	TwoArray3();//输出某一行和某一列，其余位置空白
#endif
	Half();//二分法查找
	
	return 0;
}