数据类型

• char //字符数据类型

字符a怎么表示？——‘a’ -字符a

#include<stdio.h>
int main()
{
	//字符类型
	char ch = 'a';
	//整型
	int age = 20;
	//短整型
	short num = 10;
	//long
	//long long
	//单精度浮点型
	float weight = 55.5;
	//双精度浮点型
	double d = 0.0;
	return 0;
}

• short //短整型

• int //整型

• long //长整型

• long long //长长整型

• float //单精度浮点数

• double //双精度浮点数

//

#include<stdio.h>
int main()
{
	printf("%d\n", sizeof(char));
	printf("%d\n", sizeof(short));
	printf("%d\n", sizeof(int));
	printf("%d\n", sizeof(long));
	printf("%d\n", sizeof(long long));
	printf("%d\n", sizeof(float));
	printf("%d\n", sizeof(double));
	return 0;
}

常量与变量

变量---能被改变的量

int main()
{
	int age = 20;
	double weight = 75.3;
	age = age + 1;
	weight = weight - 10;
	printf("%d\n", age);        //双字%d
	printf("%lf\n", weight);   //浮点数%lf
	return 0;
}
//%d - 整型
//%f - float
//%lf - double