Problem with LM35 code as the LED is blinking

here is the source code that using LM35 as a sensor...

here i like to experiment with the temperature produce by LM35 to produce LED output.. For example, if the temperature >>30 deg--- the LED at Pin D5 should be on...am i right...the problem....the led doesn't on...easy compulsory to connect the LED with resistor??...urgent...even if u see it might be too simple for ur guys...

#include <16F877A.H>
#device ADC=10
#fuses HS, NOWDT, NOPROTECT, BROWNOUT, PUT, NOLVP
#use delay(clock = 20000000)


#include "E:\note ngaji\FYP\stuff last sem\code\led experiment\brum\Flexlcd2.c"

//==========================


void main(void)
{
       int16 temp_adc;
       int temp;

        setup_adc(ADC_CLOCK_DIV_8);
        setup_adc_ports(PIN_A1);
        set_adc_channel(1); //read analog input from channel 1


        lcd_init();

         lcd_putc("\fTemperature:\n");

          while(1)
            {
            temp_adc = read_adc();

            temp = 5.00*temp_adc*100.00/1023.00;
         lcd_gotoxy(1,2);
            printf(lcd_putc,"%d",temp);
            delay_ms(3000);



            if ((temp<20) && (input(PIN_B7)==1))

      {
         output_high(PIN_D7);
         delay_ms(100);
      }
      else if ( (temp>= 20) && (temp_adc <30) && (input(PIN_B7)==1))
      {
         output_high(PIN_D6);
         delay_ms(100);
         }
      else if ((temp_adc >= 30) && (input(PIN_B7)==1))
         {
         output_high(PIN_D5);
         delay_ms(100);
         }
       else
      {
      output_high(PIN_D4);
      delay_ms(100);
       }
        }

}


correction

isn't compulsory to connect the LED with resistor....sorry for my english

#include <16F877A.H>
#device ADC=10
#fuses HS, NOWDT, NOPROTECT, BROWNOUT, PUT, NOLVP
#use delay(clock = 20000000)


#include "E:\note ngaji\FYP\stuff last sem\code\led experiment\brum\Flexlcd2.c"

//==========================

#define      LED1     PIN_D7
#define      LED2     PIN_D6
#define      LED3     PIN_D5
#define      LED4     PIN_D4

void main(void)
{
       int16 temp_adc;
       int temp;

        setup_adc(ADC_CLOCK_DIV_8);
        setup_adc_ports(PIN_A1);
        set_adc_channel(1); //read analog input from channel 1


        lcd_init();

         lcd_putc("\fTemperature:\n");

          while(1)
            {
            temp_adc = read_adc();

            temp = 5.00*temp_adc*100.00/1023.00;
         lcd_gotoxy(1,2);
            printf(lcd_putc,"%d",temp);


         {
            if(input(PIN_B7)==1)
         {
    if((temp<20))
   {
       //delay_ms (500);
      output_high(LED1);

   }    else
   {
      output_low(LED1);
    }

    if ((temp>= 20) && (temp_adc <30))
   {
      output_high(LED2);

     }
      else
    {
     output_low(LED2);
     }

     if ((temp_adc >= 30))
    {
       output_high(LED3);

    }
     else
     {

     output_low(LED3);
     }
       }
else

   output_high(PIN_D4);
}
        }

}