第六次图论课堂笔记

找三个数中的最大值 

代码如下

#include
int Max(int a, int b)
{
	return a > b ? a : b;
}
int main()
{
	int a = 0, b = 0, c = 0, max = 0;
	scanf_s("%d %d %d", &a, &b, &c);
	max = Max(Max(a, b), c);
	printf("max=%d", max);
	return 0;
}

找出三个数中的中间值

void swap(int* x, int *y)
{
	int tmp = *x;
	*x = *y;
	*y = tmp;
}
int Mid(int a, int b, int c)
{
	int tmp;
	if (a > b)
	{
		swap(&a, &b);
	}
	if (b > c)
	{
		swap(&b, &c);
	}
	if (a > b)
	{
		swap(&a, &b);
	}
	return b;
 }
int main()
{
	int a = 0, b = 0, c = 0, mid = 0;
	scanf_s("%d %d %d", &a, &b, &c);
	mid = Mid(a, b, c);
	printf("mid=%d", mid);
	return 0;


}

计算字符串中各种类型的个数

int main()
{
	char ch = 0;
	int consum = 0, digsum = 0, capsum = 0, smasum = 0, othsum = 0;
	while (ch = getchar(), ch != 'n')
	{
		if (iscntrl(ch))
		{
			consum += 1;
			continue;
		}
		if (isdigit(ch))
		{
			digsum += 1;
			continue;
		}
		if (isupper(ch))
		{
			capsum += 1;
			continue;
		}
		if (islower(ch))
		{
			smasum += 1;
			continue;
		}
			othsum += 1; 
	}	
	
		printf("consum: %d n", consum);
		printf("digsum: %d n", digsum);
		printf("capsum: %d n", capsum);
		printf("smasum: %d n", smasum);
		printf("othsum: %d n", othsum);
		return 0;
	
	}

空指针不能进行解引用

定义指针时一定要初始化，从而避免野指针

形参不能改变实参的值