2009 求数列的和

#define _CRT_SECURE_NO_WARNINGS 1

#include <stdio.h>
#include <math.h>
int main()
{

double n,m;
while(scanf("%lf%lf",&n,&m)!=EOF)
{
    double sum = n;
    int i = 0;
    if(m<1000 && n<10000)
    {   
        for(; i<m-1; i++)
        {
            n = sqrt(n);
            sum += n;
        }
        printf("%.2f\n",sum);
    }
}
return 0;

}

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2010 水仙花数

#define _CRT_SECURE_NO_WARNINGS 1

#include <stdio.h>
int main()
{

int m,n;
while(scanf("%d%d",&m,&n)!=EOF)
{
    if(m>=100 && n<=999 &&m<=n)
    {
        int a,b,c,i,flag;
        flag = 0;
        for(i=m; i<=n; i++)
        {
            a = i/100;
            b = i/10%10;
            c = i%10;
            if(i==(a*a*a + b*b*b + c*c*c))
            {
                if(flag==1)
                    printf(" ");//防止输出格式错误，最后的数后面没有空格
                printf("%d",i);
                flag = 1;
            }

        }
        if(flag==0)
            printf("no\n");
        else
            printf("\n");
    }
}
return 0;

}

--------------------------------------------------

2011 多项式求和

#define _CRT_SECURE_NO_WARNINGS 1

#include <stdio.h>

int main()
{

int m,n,j;
double tmp;
while(scanf("%d",&m)!=EOF)
{
    if(m<100)
    {
        while(m--)
        {
            double ret = 0.0;
            scanf("%d",&n);
            if(n<1000)
            {
                for(j=1; j<=n; j++) 
                {
                    tmp = 1.0 / j;
                    if(j%2==0)
                        ret = ret - tmp;
                    else
                        ret = ret + tmp;
                }
                printf("%.2lf\n",ret);
            }
        }           
    }       
}
return 0;

}