writing user-defined functions and 'for loop'

#include <p18f4520.h>
#include <delays.h>

//2.0 Configure Controller
#pragma config OSC = HS //set external High-speed (HS) oscillation
#pragma config WDT = OFF //disable the Watchdog feature of the MCU
#pragma config LVP = OFF //disable low voltage programming (LVP)
#pragma config PBADEN = OFF //Port B Analogue to Digital module is OFF

//3.0 Definition: define which pin each LED is connected to using bit-oriented instruction
#define L0 PORTCbits.RC0 //RC0 assigned as L0
#define L7 PORTCbits.RC7 //RC7 assigned as L7

//4.0 user define functions

//declare and define a long delay for 1:2
void delay_long(void)
{
 int x;
 for(x; x<20000;x++)
 {
   // do nothing for 20000 times
 }
}
//declare and define a short delay for 1:1
void delay_short(void)
{
 int x;
 for(x=0; x<10000;x++)
 {
  //do nothing for 10000 times
 }
}

//function for LED7 (1:1) and LED0 (0)
void display_1(void)
{
 L0=0;
 L7=1;
 delay_short();
 L7=0;
 delay_short();
}

//function for LED7 (0) and LED0 (2:1)
void display_2(void)
{
 L7=0;
 L0=1;
 delay_long();
 L0=0;
 delay_short();
}

//5.0 start of main program
void main(void)
{
//5.1 Declare variables
int i;

//5.2 configure I/O ports
 TRISCbits.TRISC0 =0; //configure only RC0 as output
 TRISCbits.TRISC7 =0; //configure only RC7 as output

//5.3 initialize variables and output ports
i=0; //assign 0 to interger i
PORTCbits.RC0 = 0; // clear bit RC0 only using a bitwise instruction
PORTCbits.RC7 = 0; // clear bit RC7 only using a bitwise instruction

// infinite loop
while(1)
{
 L0=0; //off both LEDs
 L7=0;

 Delay10KTCYx(3000); // 3 sec delay @4Mhz oscillator

 for(i=0; i<5;++) // loop 5 times
 {
  display_1(); //call the display_1() function
 }
 Delay10KTCYx(3000); //3 sec delay @4Mhz oscillator

 for(i=10; i<10; i++) // loop 10 times
 {
 display_2(); //call the display_2() function
 }

 Delay10KTCYx(3000); // 3 sec delay @4Mhz oscillator

 for(i=0; i<10;i++) //loop 10 times
 {
  L0=1; //on both LEDS
  L7=1;
  delay_short(); //call delay_short() function
  L0=0; //off both LEDS
  L7=0;
  delay_short(); //call delay_short() function
  }
 } //end of while loop
} //end of main program