C :

#include<stdio.h>
int main()
{
	int n,k,i=1;
    scanf("%d",&n);
	while(i <= n)
	{
		k = 1;
	    while (k <= i)
		{
	       printf("%d",k);
		   k = k + 1;
		   if (k <= i)
		   {
		     printf(" ");
		   }
		}
		printf("\n");
		i = i + 1;
	}
	return 0;
}

C++ :

#include<stdio.h>
int main()
{
	int n,i,j,count;
	scanf("%d",&n);
	for(i = 1 ; i <= n ; i ++)
	{
		for(j = 1 ; j <= i;j ++)
		{
			count ++;
			if ( j == 1)
				printf("%d",1);
			else if (j != 1)
				printf(" %d",j);
		}
			
		printf("\n");
	}
	return 0;
}

Pascal :

program xzy1;
  var
    n,i,j:integer;
  begin
    readln(n);
    for i:=1 to n do
      begin
      for j:=1 to i-1 do
        write(j,' ');
        writeln(i);
      end;
  end.