if(!(IN0&IN1)) OUT0=1; else OUT0=0;

/*
 * Project name:
     NAND operator  
 
 *  MCU:             PIC16f877A
     Oscillator:      4 MHz
*/
sbit OUT0 at PORTD.B0; // this is where OUTPUT OUT0 is fully defined
sbit OUT1 at PORTD.B1; // this is where OUTPUT OUT1 is fully defined
sbit OUT2 at PORTD.B2; // this is where OUTPUT OUT2 is fully defined
sbit OUT3 at PORTD.B3; // this is where OUTPUT OUT3 is fully defined
sbit OUT4 at PORTD.B4; // this is where OUTPUT OUT4 is fully defined
sbit OUT5 at PORTD.B5; // this is where OUTPUT OUT5 is fully defined
sbit OUT6 at PORTD.B6; // this is where OUTPUT OUT6 is fully defined
sbit OUT7 at PORTD.B7; // this is where OUTPUT OUT7 is fully defined
sbit IN0 at PORTC.B0; // this is where INPUT IN0 is fully defined
sbit IN1 at PORTC.B1; // this is where INPUT IN1 is fully defined
sbit IN2 at PORTC.B2; // this is where INPUT IN2 is fully defined
sbit IN3 at PORTC.B3; // this is where INPUT IN3 is fully defined
sbit IN4 at PORTC.B4; // this is where INPUT IN4 is fully defined
sbit IN5 at PORTC.B5; // this is where INPUT IN5 is fully defined
sbit IN6 at PORTC.B6; // this is where INPUT IN6 is fully defined
sbit IN7 at PORTC.B7; // this is where INPUT IN7 is fully defined
void main(){
  
  TRISD = 0;        // set PORTD as Output
  TRISC = 0XFF;  // PORTC as Inputs
  PORTD = 0 ;  //Clear Outputs
  while (1) {           // endless Loop 
    if((!IN0)&(!IN1)) OUT0=1; else OUT0=0;// if input0 NAND input1 is true , output0 will be ON else OFF
    //if(!(IN0|IN1)) OUT0=1; else OUT0=0;
  }
}