C Language and program design preliminary routines-26 solve problems with switch statements __c language

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Application: Calculate freight
The basic freight rates per ton of cargo per kilometer are p (price), the goods are w (weight), the distance is s, the discount is D (discount), then the total freight f (freight) is calculated as freight=price*weight*s* (1-discount )

#include <stdio.h>
int main ()
{
    int c,s;
    float p,w,d,f;
    printf ("Please enter p,w,s:");
    scanf ("%f%f%d", &p, &w, &s);
    if (s>=3000)
        c=12;
    else
        c=s/250;
    Switch (c)
    {case
    0:
        d=0;break;
    Case 1:
        d=2;break;
    Case 2: Case
    3:
        d=5;break;
    Case 4: Case
    5: Case
    6: Case
    7:
        d=8;break;
    Case 8: Case 9: Case:
        d=10;break;
    Case:
        d=15;break;
    f=p*w*s* (1-d/100.0);
    printf ("freight=%.2f\n", f);
    return 0;
}

Using switch to find piecewise functions

#include <stdio.h>
#include <math.h>
int main ()
{
    double x, y;
    int t;
    scanf ("%lf", &x);
    T= (x<2) + (x<6) + (x<10);
    Switch (t)
    {
    Case 3://(X<2), (x<6), (x<10) y=x when all is true
        ;
        break;
    Case 2://(x<6), (x<10) is true
        y=x*x+1;
        break;
    Case 1://only (x<10) is true when
        y=sqrt (x+1);
        break;
    Case 0:  //(X<2), (x<6), (X<10) No one is true, that is, x>=10
        y=1/(x+1);
    printf ("%lf\n", y);
    return 0;
}