学习期间，将写内容过程较好的内容段备份一下，下边内容段是关于C语言基础：if条件语句使用演示的内容，应该是对各位朋友有所用。
#include <stdio.h>
void main ()
{
int age = 21;
int height = 73;
if (age == 21)
printf("User's age is 21n");
if (age != 21)
printf("User's age is not 21n");
if (height == 73)
printf("User's height is 73n");
if (height != 73)
printf("User's height is not 73n");
}