Method One:
#include <stdio.h>
#include <math.h>
Double fun (int m)
{
int n,i,k;
double s = 0.0;
for (n=3;n<=m;n++)
{
K = sqrt (n);
for (i=2;i<=k;i++)
if (n%i==0) break; If n is composite, end this layer for loop
if (i>=k+1) s + = sqrt (n); I can not be exhausted by N, then N is prime number
}
return s;
}
void Main ()
{
int m;
Double S;
FILE *out;
printf ("\n\ninput m:");
scanf ("%d", &m);
s = Fun (M);
printf ("\n\ns=%f\n\n", s);
}
Method Two:
#include <stdio.h>
#include <math.h>
Double fun (int m)
{
/*
int n,i,k;
double s = 0.0;
for (n=3;n<=m;n++)
{
K = sqrt (n);
for (i=2;i<=k;i++)
if (n%i==0) break;
if (i>=k+1) s + = sqrt (n);
}
*/
int i,j;
double s = 0.0;
for (i=3;i<=m;i++)
{
for (j=2;j<i;j++)
{
if (i%j = = 0) break;
}
if (J >= i)
s = s + sqrt (i);
}
return s;
}
void Main ()
{
int m;
Double S;
FILE *out;
printf ("\n\ninput m:");
scanf ("%d", &m);
s = Fun (M);
printf ("\n\ns=%f\n\n", s);
}
Sum of the squares of primes in C language