明解C语言 入门版

第二章 运算和数据类型

从0开始的C语言学习：）
为了练习英语，我尽量用英文写代码和注释

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2-1 运算

练习2-1

显示出前者是后者的百分之几：

#include 
int main(void)
{
	int vx,vy;

	puts("请输入两个整数。");

	printf("整数a、整数b:\n");   scanf_s("%d%d", &vx,&vy );

	printf("a是b的%d%%。\n",100*vx/vy);

	return 0;
}

练习2-2

读取两个整数然后输出它们的和，积：

#include 
int main(void)
{
	int x, y;
	puts("please input two integer:");  scanf_s("%d%d", &x, &y);
	printf("sum=%d multiply=%d",x+y,x*y);
	return 0;
}

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2-2 数据类型

练习2-3

读出两个实数的值：

#include 
int main(void)
{
	double x;
	double y;

	puts("please put x,y:");
	printf("double x:");  scanf_s("%lf", &x);
	printf("double y:");  scanf_s("%lf", &y);

	printf("%f\n%f",x,y);
	return 0;
}

练习2-4

对整型常量、浮点型常量、int型变量和double型变量进行乘除等各种运算：

#include 
int main(void)
{
	int n1, n2, n3, n4;
	double d1, d2, d3, d4;
	int x;
	double y;

	puts("please input x,y:");
	printf("put x:");  scanf_s("%d",&x);
	printf("put y:");  scanf_s("%lf",&y);
	printf("division x=%d multiply x=%d\n", x / 2,x*2);
	printf("division y=%f multiply y=%f\n\n", y / 2.0,y*2.0);

	n1 = 5 / 2;
	n2 = 5.0 / 2.0;
	n3 = 5.0 / 2;
	n4 = 5 / 2.0;

	d1 = 5 / 2;
	d2 = 5.0 / 2.0;
	d3 = 5.0 / 2;
	d4 = 5 / 2.0;

	printf("n1=%d\n", n1);
	printf("n2=%d\n", n2);
	printf("n3=%d\n", n3);
	printf("n4=%d\n\n", n4);

	printf("d1=%f\n", d1 );
	printf("d2=%f\n", d2);
	printf("d3=%f\n", d3);
	printf("d4=%f\n", d4);

	return 0;
}

练习2-5

计算前者是后者的百分之几，并用实数输出结果：

#include 
int main(void)
{
	int x, y;

	puts("please input two integer:");
	printf("int x:"); scanf_s("%d", &x);
	printf("int y:"); scanf_s("%d", &y);

	printf("x的值是y的%f %%。\n",(double)(100*x/ y));

	return 0;
}

练习2-6

读取表示身高的整数值，显示出标准体重的实数值。标准体重根据公式（身高-100）*0.9进行计算，所得结果保留一位小数：

#include 
int main(void)
{
	double h;
	printf("please input your height;");  scanf_s("%lf", &h);
	printf("your standard weight is :%.1f kg", (h - 100) * 0.9);

	return 0;
}

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