Test3_27_初识C语言.rar

#include<stdio.h> //头文件 stdio.h 标准输入输出头文件 void main() { int a, b, sum; printf("please input a and b:>"); scanf("%d %d", &a, &b); //&a 取a变量的地址 //scanf("%d,%d", &a, &b); //&a 取a变量的地址 sum = a + b; printf("sum = %d\n", sum); } /* void main() { int a = 100; int b = 200; int sum = a + b; printf("sum = %d\n", sum); } /* void main() { int a = 10; printf("a = %d\n", a); { int b = 100; printf("a = %d\n", a); printf("b = %d\n", b); } printf("a = %d\n", a); printf("b = %d\n", b); } /* //全局变量 int global = 100; void main() { //局部变量 int a = 0; printf("a = %d\n", a); //局部变量 int global = 20; printf("global = %d\n", global); } /* void main() { //尽量的初始化 int i = 0; printf("i = %d\n", i); int a; a = 0; //赋值 a = 1; a = 10; } /* void main() { //变量 char ch = 'A'; // int i = 100; double d = 12.34; i = 1000; //ch = 'X'; printf("ch = %c\n", ch); printf("i = %d\n", i); printf("d = %lf\n", d); } /* void main() { printf("%d\n", sizeof(char)); //1 printf("%d\n", sizeof(short)); //2 printf("%d\n", sizeof(int)); //4 printf("%d\n", sizeof(float)); //4 printf("%d\n", sizeof(double)); //8 } /* //类型 //整形 char short int long 不带小数点 10 100 //浮点数 float double 带小数点的数据 1.23 2.5 void main() { //定义变量, 为变量开辟内存空间 char ch; short s; int i; float f; double d; } /* void main() { char ch; short s; int i; long g; float f; double d; } /* void main() { printf("Hello C.\n"); } /* void main() { printf("Hello C++.\n"); } /* int main() //必须要有主函数 { return 0; } /* 注释 void main() { int m; scanf("%d", &m); printf("m = %d\n", m); printf("Hello C.\n"); } */