[SOLVED] PIC16F877a temperature control program using CCS C [if statement not executed]

Code C - [expand]
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/* 
PIC16F877A and LM35 Based Temperature Monitor 
 
MACHI M.C 
STD.no 20403715
*/ 
 
#include <16f877a.h> 
#device adc=10    // Set ADC resolution to 10Bit
#fuses XT,NOLVP,NOWDT,NOPROTECT 
#use delay(crystal=4000000)
#use rs232(baud=960,xmit=PIN_C6,rcv=PIN_C7,ERRORS)
#include <lcd.c>
 
#define  LOAD  PIN_B7
#define  THRES 70.0     // load switching threshold in Celsius
#define  OFF 50.0  // fan stops when temparature reaches value in degrees
#define ADC_OFF 0   // ADC off
#define  RELAY PIN_B4
#define  R2    PIN_B2
#define  R1    PIN_B1
#include <stdlib.h>
int16 digital_reading;  // ADC resolution is 10Bit, an 8Bit integer is not enough to hold the reading
float temp;
 
 
 
void main()
{
  
   /* ADC Initialization */
   setup_adc(ADC_CLOCK_INTERNAL); // initialize ADC with a sampling rate of Crystal/4 MHz
   setup_adc_ports(RA0_ANALOG);   // set PIN_A0 as analog input channel
   set_adc_channel(0);            // point ADC to channel 0 for ADC reading
   delay_ms(1);                   // ADC module is slow, needs some time to adjust.
  
   disable_interrupts(GLOBAL);   // DISABE ALL INTERRUPTS.
   SET_TRIS_B(0X0F);             //set RB0,RB1,RB2 & RB3 as inputs, RB4,RB5,RB6 & RB7 as output.
 output_low(RELAY);            // relay initialy off
   if (input(PIN_B2)==0)
   {
   output_high(PIN_B4);
   }
   else if (input(PIN_B2)==1)
   {
   output_low(RELAY);
   }
   
   /* Peripherals Configurations */
   lcd_init();                   // Turn LCD ON, along with other initialization commands
   output_low(LOAD);             // the load is initially OFF
   lcd_gotoxy(1,1);              // point LCD cursor to col1 row1
   lcd_putc("Temperature is:");  // print on LCD
   {
   while(1) // infinite loop
   {
      digital_reading = read_adc();    // capture current temperature reading
      delay_us(100);                   // 0.1ms delay for ADC stabilization
      temp = digital_reading * 0.4883; // convert reading to Celsius
      lcd_gotoxy(1,2);                 // point LCD cursor to col1 row2
      printf(lcd_putc,"%2.1f C",temp); // print value on LCD
 
      if(temp>=THRES)
       Do 
       {
         output_high(LOAD);   // Control Load
       }
      while (temp>=OFF);
      else  output_low(LOAD);
      delay_ms(1000);   // 1 second delay between readings
   }
   }
}

Code C - [expand]
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if (input(PIN_B2)==0)
   {
   output_high(PIN_B4);
   }
   else if (input(PIN_B2)==1)
   {
   output_low(RELAY);
   }