Solution of Prime number (C language)

1. Enter all the primes between 100 and 200.

(1) through a two-tier for loop

#include <stdio.h>

int main ()

{

int i;

Int J;

for (i=100;i<=200;i++)

{

for (j=2;j<=i-1;j++)

{

if (i%j==0)

Break

}

if (j==i)

printf ("%d", I);

}

return 0;

}

Optimization:

#include <stdio.h>

int main ()

{

int i;

Int J;

for (i=101;i<=200;i=i+2)

{

for (j=2;j<=i/2;j++)

{

if (i%j==0)

Break

}

if (J>=I/2)

printf ("%d", I);

}

return 0;

}

(2) by comparing the number of records

#include <stdio.h>

int main ()

{

int i,j;

int count=0;

for (i=100;i<=200;i++)

{

count=0; Each time count needs to start at 0

for (j=2;j<=i-1;j++)

{

if (i%j==0)

Break

Else

count++;

}

if (count==i-2)//Record Count comparison

printf ("%d", I);

}

return 0;

}

(3) Boolean type

#include <stdio.h>

int main ()

{

int i,j;

BOOL Flag;

for (i=100;i<=200;i++)

{

Flag = true;

for (j=2;j<=i-1;j++)

{

if (i%j==0)

{

Flag=false;

Break

}

}

if (flag)

printf ("%d", I);

}

return 0;

}

Note: Applying a Boolean type is not possible in VC6.0. Can be implemented in Microsoft Visual Studio 2008.

Solution of Prime number (C language)