basic pattern programs in c

Basic pattern programs in c

These programs print various patterns of numbers and stars. These codes illustrate how to create various patterns using c program. The C programs involve usage of nesting while loops (a while loop inside a while loop). A pattern of numbers or star or characters is a way of arranging these in some logical manner or they may form a sequence. Some of these patterns are triangles which have special importance in mathematics. Some patterns are symmetrical while others are not.

Example#1

#include <stdio.h>
int main()
{
  int i,n,in;
  printf("Enter a value: ");
  scanf("%d",&n);
  i=1;
  while(i<=n)   // Loop to print rows (outer loop)
  {
    printf("\n");
    in=1;
    while(in<=i) .   // Loop to print numbers
    {
      printf("%d",in);
      in=in+1;
    }
    i=i+1;
  }
  
  return 0;
}

[quote]

Output:                                                                                                                                                          

[/quote]

For the above program, if we change the inner loop print statement as printf("*") then print following output pattern

in=1;
while(in<=i)
{
   printf("*"); //prints all '*'
   in=in+1;
}

in=1;
while(in<=i)
{
   /*
       - First number of every row i.e. in == 1
       - Last number of every row i.e. i == in
       - Last row of pattern i.e. i== n 
   */
   if (in == 1 || i == in || i == n)
     printf("*");
   else 
     printf("%d",in);
   in=in+1;
}

 in=1;
 while(in<=i)
 {
   if(i%2 == 0)  // if the row value is evern i.e. i%==2 
    printf("*");
   else 
    printf("%d",in);
      in=in+1;
 }

 in=1;
 while(in<=i)
 {
   if(in%2 == 0)  // if the number value is evern i.e. i%==2 
    printf("*");
   else 
    printf("%d",in);
      in=in+1;
 }

 in=1;
 while(in<=i)
 {
   if(i%2 != in%2)  // if  i value even and in value is odd or vice versa 
    printf("*");
   else 
    printf("%d",in);
      in=in+1;
 }

 in=1;
 while(in<=i)
 {
   printf("%d",i);
   in=in+1;
 }

#include <stdio.h>
int main()
{
  int i,n,in,value=1;
  printf("Enter a value: ");
  scanf("%d",&n);
  i=1;
  while(i<=n)
  {
    printf("\n");
    in=1;
    while(in<=i)
    {
        printf("%3d",value);
        value= value + 1;
        in=in+1;
    }
    i=i+1;
  }
  
  return 0;
}

#include <stdio.h>
int main()
{
  int i,n,in;
  printf("Enter a value: ");
  scanf("%d",&n);
  i=1;
  while(i<=n)
  {
    printf("\n");
    in=i;
    while(in>=1)
    {
        printf("%d",in);
        in=in-1;
    }
    i=i+1;
  }
  
  return 0;
}

in=1;
while(in<=i)
{
  if (in%2 == 0)
    printf("%d",2);
  else 
    printf("%d",1);
  in=in+1;
}