题目一：计算两个班的人数

#include<stdio.h>

int main()
{
   int firstNum=54;
   int secondNum=52;
   printf("firstNum+secondNum=%d",54+52);
   return 0;
}

题目二：取余运算

#include<stdio.h>

int main()
{
   int firstNum=54;
   printf("firstNum/4=%d",54/4);
   return 0;
}

题目三：求差值

#include<stdio.h>

int main()
{
   int firstNum=54;
   int secondNum=52;
   printf("firstNum-secondNum=%d",54-52);
   return 0;
}

题目四：输入操作

#include <stdio.h>

int main()
{
   int firstNum=0;
   int secondNum=0; 
   int total=0.0;
   printf ("请输入一班的人数:\n");
   scanf ("%d",& firstNum); 
   printf ("请输入二班的人数:\n");
   scanf ("%d",& secondNum);
   printf ("该专业的总人数为：%d\n",total);
   return 0;
}