#include<stdio.h>
#include<math.h>
void main()
{
    int p,w,s;
    float f;
    printf("input three numbers p,w,s\n");
    scanf("%d %d %d",&p,&w,&s);
    switch(s)
    {
        case 's<25':printf("f=p*w*s*1=%f",f);break;
        case '250<=s<50':printf("f=p*w*s*0.98=%f",f);break;
        case '500<=s<100':printf("f=p*w*s*0.95",f);break;
        case '1000<=s<200':printf("f=p*w*s*0.92=%f",f);break;
        case '2000<=s<300':printf("f=p*w*s*0.90=%f",f);break;
        case '3000<=':printf("f=p*w*s*0.85=%f",f);break;
        default:("错误");break;
    }
}
我输入数据后，可未显示结果，结果是个空的，我感觉case后面那种类型可能是错误的？请大佬们帮忙解决一下我的疑惑？？??

参见： https://zh.

#include <stdio.h>

int main( void )
{
    unsigned p,w,s;
    puts( "input three numbers p,w,s" );
    if( scanf("%d%d%d",&p,&w,&s) != 3 )
    {
        puts( "输入错误" );
        return 1;
    }

    double f;
    switch( s/250 )
    {
    case  0: f=1.00; break;
    case  1: f=0.98; break;
    case  2:
    case  3: f=0.95; break;
    case  4:
    case  5:
    case  6:
    case  7: f=0.92; break;
    case  8:
    case  9:
    case 10:
    case 11: f=0.90; break;
    default: f=0.85;
    }
    printf( "%f\n", p*w*s*f );

    return 0;
}