第四次作业

#include<stdio.h>
main(){
    int mark;
    pringtf("请输入学生分数(0-100):\n");
    scanf("%d",&mark);
    switch(mark/10)
    {
    case 10:
       case 9:printf("A\n");
       case 8:printf("B\n");
       case 7:printf("C\n");
       case 6:printf("D\n");
       default:printf("NO PASS!\n");
    }
}

 

#include<stdio.h>
main(){
    float x,y;
    printf("请输入x的值：\n");
    scanf("%f",&x);
    if(x>0)
        y=x*x+1;
    else if(x==0)
        y=0;
    else
        y=-x*x+1;
    printf("x=%.1f\ny=%.1f\n",x,y);
}

 

#include<stdio.h>
main(){
    float n1,n2;
    char sign;
    printf("请输入计算机的表达式：\n");
    scanf("%f%c%f",&n1,&sign,&n2);
    switch(sign){
    case'+':printf("n1+n2=%f\n",n1+n2);break;
    case'-':printf("n1-n2=%f\n",n1-n2);break;
    case'*':printf("n1*n2=%f\n",n1*n2);break;
    case'/':printf("n1/n2=%f\n",n1/n2);break;
    }
}

 

#include<stdio.h>
main(){
    int a,b,c,max;
    scanf("%d%d%d",&a,&b,&c);
    max=a>b?a:b;
    max=max>c?max:c;
    printf("%d\n",max);
}

 

#include<stdio.h>
main(){
    int m;
    scanf("%d",&m);
    if(m/4==0&&m/6==0)
        printf("nengbeizhengchu\n");
    else
        printf("bunengbeizhengchu\n");
}

 

#include<stdio.h>
main(){
    int m;
    printf("qingshurunianfen");
    scanf("%d",&m);
    if(m/4==0||m/400==0&&m/100!=0)
        printf("runnian\n");
    else
        printf("pingnian\n");
}