Temperature display using LM35 Seven Segment Display Multiplexing + ADC of PIC16F876A

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#pragma config FOSC=HS, LVP=OFF, WDTE=OFF
#include<stdio.h>
#include<pic16f876a.h>
#include<xc.h>
#define _XTAL_FREQ 20000000
 
void MSDelay(int itime);
void fnd_display(int val,int pos);
void read_adc(void);
unsigned char lup[10]={0x81,0xF3,0x49,0x61,0x33,0x25,0x05,0xF1,0x01,0x21};
unsigned int result;
int digits[2];
 float n;int temp,rs;
void main() {
    CMCON=7; //Comperator off
    TRISB=0;
    TRISAbits.TRISA0=1;
    TRISC=0;
    ADCON0=0b10000000;        
    ADCON1=0b11000000;        // select right justify result. A/D port configuration 0
    ADCON0bits.ADON=1;                // turn on the A2D conversion module
    MSDelay(30);
 
 
    while(1){
          read_adc();
          n=result*0.48876;
          //n+=0.5;
          temp=n;
          rs=temp;
          digits[0]=rs%10;
          digits[1]=rs/10;
          fnd_display(digits[1],0);
          MSDelay(50);
          fnd_display(digits[0],1);
          MSDelay(20);
          }
 
    }
 
void read_adc(void)
{
        unsigned short i;
        unsigned long result_temp=0;
      for(i=500;i>0;i-=1) //looping 500 times (better 2000 times) for getting average value
      {
        ADCON0bits.GO = 1; //ADGO is the bit 2 of the ADCON0 register
        while(ADCON0bits.GO==1); //ADC start, ADGO=0 after finish ADC progress
        result=ADRESH;
        result=result<<8; //shift to left for 8 bit
        result=result|ADRESL; //10 bit result from ADC
        result_temp+=result;
        //MSDelay(1);
         }
result = result_temp/500; //getting average value
 }
 
void MSDelay(int itime){
     int i,j;
    for(i=0;i<itime;i++)
        for(j=0;j<135;j++);
        return;
}
void fnd_display(int val,int pos){
 
switch(pos){
 
case 0:
PORTC=0b00010000;
break;
case 1:
PORTC= 0b00100000;
break;
}
PORTB=lup[val];
return ;
}