C :

#include<stdio.h>   

int main(){ 
	int x;
	scanf("%d",&x);
	
	int a = x / 100;
	int b = x / 10 % 10;
	int c = x % 10;
	
	
	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;
	}
	
	printf("%d",a * 100 + b * 10 + c);

	return 0;
} 

C++ :

#include<iostream>
using namespace std;
int main(){
	int a,b,c,n,t,x;
	cin>>n;
	a=n/100;
	b=n/10%10;
	c=n%10;
	//cout<<a<<" "<<b<<" "<<c<<endl;
	
	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=t;
	}
	x=c*100+b*10+a*1;
	cout<<x<<endl;
}

Python :

a = int(input());
b = a // 100;
s = a // 10 % 10;
g = a % 10;
if b < s :
    t = b;
    b = s;
    s = t;

if b < g :
    t = b;
    b = g;
    g = t;

if s < g :
    t = s;
    s = g;
    g = t;

print(b * 100 + s * 10 + g);