C :

#include<stdio.h>   

int main(){ 
	int a,b,c;
	scanf("%d %d %d",&a,&b,&c);
	
	if(a < b){
		int t = a;
		a = b;
		b = t;
	}
	
	if(b < c){
		int t = b;
		b = c;
		c = t;
	}
	
	if(a < b){
		int t = a;
		a = b;
		b = t;
	}
	
	if(a - b == 1 && b - c == 1){
		printf("TRUE");
	}else{
		printf("FALSE");
	}

	return 0;
} 

C++ :

#include<iostream>
using namespace std;
int main(){
	int a,b,c,t;
	cin>>a>>b>>c;
	if(a>b){
		t=a;
		a=b;
		b=t;
		
	}
	if(b>c){
		t=b;
		b=c;
		c=t;
	}
	if(a>b){
		t=a;
		a=b;
		b=c;
	}
	if(c-1==b&&b-1==a){
		cout<<"TRUE"<<endl;
	}else{
		cout<<"FALSE"<<endl;
	}
	
}

Pascal :

var a,b,c,t:longint;
begin
  read(a,b,c);
  if a<b then begin t:=a;a:=b;b:=t; end;
  if b<c then begin t:=b;b:=c;c:=t; end;
  if a<b then begin t:=a;a:=b;b:=t; end;
  if (a-1=b)and(b-1=c)and(c+2=a) then
   writeln('TRUE') else
    writeln('FALSE');
end.

Java :

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		@SuppressWarnings("resource")
		Scanner scanner=new Scanner(System.in);
		int x=scanner.nextInt();
		int y=scanner.nextInt();
		int z=scanner.nextInt();
		if (((2*x==y+z)&&(x-y==1||x-z==1))||((2*y==x+z)&&(y-x==1||y-z==1))||((2*z==y+x)&&(z-y==1||z-x==1)))
		
		System.out.print("TRUE");	
		else System.out.print("FALSE");	
		}
}

Python :

a,b,c = map(int,input().split());
# a>b>c
if a < b:
    t=a
    a=b
    b=t 
if a < c:
    t=a
    a=c
    c=t 
if b < c:
    t=b
    b=c
    c=t
if a-b==1 and b-c==1:
    print('TRUE')
else :
    print('FALSE')