实验

 

#include<stdio.h>
int main(void)
{
    double R,s;

    printf("Enter R:");
    scanf("%lf",&R);
    if(R<=0){
        printf("You are wrong.
");
    }
    else{
        s=3.14*R*R;
        printf("f(%.2f)=%.2f
",R,s);
    }
    
    return 0;
}

#include<stdio.h>
int main(void)
{
    int i,n;
    double R,V,H;

    printf("Enter n:");
    scanf("%d",&n);
    printf("Enter H:");
    scanf("%Lf",&H);
    printf("Enter R:");
    scanf("%Lf",&R);

    if(R,H<=0){
        printf("你的输入有误。
");
    }
    else{
        for(i=1;i<=n;i++){
            V=3.14*R*R*H*i;
            printf("V=%.2f
",V);
        }
    }

    return 0;
}

#include<stdio.h>
int main()
{
    int c1,c2,c3,c4;
    scanf("%d%d",&c1,&c2);
    printf("%d
",c1+c2);

    getchar();
    c3 = getchar();
    c4 = getchar();

    printf("%d
",c3+c4);
    return 0;
}

#include<stdio.h>
int main()
{
    char c1,c2,c3,c4;
    scanf("%c%c",&c1,&c2);
    printf("%c %c
",c1,c2);
    getchar();
    c3 = getchar();
    c4 = getchar();
    printf("%c %c
",c3,c4);
    printf("%c %c %c %c
",c1,c2,c3,c4);
    return 0;
}