作业八总结

#include<stdio.h>
int fact(int i);
int main()
{
    int n,i;
    double e,num;
    printf("Input n:");
    scanf("%d",&n);
    for(i=1;i<=n;i++){
        num=fact(i);
        e=e+num;
    }
    printf("和为：%.0lf",e);
    return 0;
}

int fact(int i)
{
    int sum=1,n,j;
    for(j=1;j<=i;j++)
    sum=sum*j;
    return sum;
}

#include<stdio.h>
int main()
{
    int m,n;
    double i,sum=0,num;
    printf("Input m,n:");
    scanf("%d%d",&m,&n);
    for(i=m;i<=n;i++){
        num=i*i+1/i;
        sum=sum+num;
    }
    printf("和为:%.6lf",sum);
    return 0;
}

#include<stdio.h>
int main()
{
    int n,fh=1,i;
    double fm=1,fz=1,sum=0,num;
    printf("Input n:");
    scanf("%d",&n);
    for(i=1;i<=n;i++){        
        num=fh*(fz/fm);
        fh=-fh;
        fm=fm+2;
        fz=fz+1;
        sum=sum+num;        
    }
    printf("和为：%.2lf",sum);
    return 0;    
}

#include<stdio.h>
int main()
{
    int a,b,c,d;
    double sum,p;
    printf("Input 4 number:");
    scanf("%d%d%d%d",&a,&b,&c,&d);
    sum=a+b+c+d;
    p=sum/4;
    printf("和=%.lf 平均值=%.1f",sum,p);
    return 0;
}

#include<stdio.h>
int main()
{
    int x;
    double d;
    printf("Input x:");
    scanf("%d",&x);
    if(x<=50) d=x*0.53;
    else d=(x-50)*0.58+50*0.53;
    printf("电费为:%.1lf",d);
    return 0;
}  

#include<stdio.h>
#include<math.h>
int main()
{
    int i,n;
    double sum=0,num;
    printf("Input n:");
    scanf("%d",&n);
    for(i=1;i<=n;i++){
        num=sqrt(i);
        sum=sum+num; 
    }
    printf("和为：%.2lf",sum);
    return 0;
}