main.c: In function 'is_Prime': 
 main.c:29:1: error: expected declaration specifiers before 'for' 
  for(j = 2; j < k; j++) 
  ^ 
 main.c:29:12: error: expected declaration specifiers before 'j' 
  for(j = 2; j < k; j++) 
  ^ 
 main.c:29:19: error: expected declaration specifiers before 'j' 
  for(j = 2; j < k; j++) 
  ^ 
 main.c:42:1: error: expected declaration specifiers before '}' token 
  } 
  ^ 
 main.c:42:1: error: expected '{' at end of input 
 main.c: In function 'main': 
 main.c:42:1: error: expected declaration or statement at end of input

#include <stdio.h>
 #include <math.h>
 
 main()
 {
  int n;
  int k;
  int j;
 
 //gets user input for length of string
  printf("Enter the value of n:");
  scanf("%d", &n);
 //stores user input as n
 
  printf("Printing primes less than or equal to %d: \n", n);
 
  for(k = 2; k <= n; k++)
  {
  if(is_Prime(k) == 1)
  {
  printf("%d,", k);
  }
  }
 
 
  //here is the is_Prime function
 {
 int is_Prime (int k)
 
 
 for(j = 2; j < k; j++)
  {
 if(k%j != 0)
  {
  return 1;
  }
 
 else if(k%j == 0)
  {
 return 0;
 break;
  }
  } 
 }