C :

#include <stdio.h>
void main()
{
	int n,b,s,g,t;
	scanf("%d",&n);
	b=n/100;
	s=n%100/10;
	g=n%10;
	if(b>s){
		t=b;
		b=s;
		s=t;
	}	
	if(s>g){
		t=s;
		s=g;
		g=t;
	}
	if(b>s){
		t=b;
		b=s;
		s=t;
	}
	if(b==0){
		t=b;
		b=s;
		s=t;	
	}
	printf("%d",b*100+s*10+g);
}

C++ :

#include <bits/stdc++.h>

using namespace std;

int main(){
	int t,n,a,b,c;
	cin>>n;
	a=n/100;
	b=n/10%10;
	c=n%10;
	if(a>b){
		t=a;
		a=b;
		b=t;
	}
	
	if(b>c){
		t=c;
		c=b;
		b=t;
	}
	
	if(a>b){
		t=a;
		a=b;
		b=t;
	}
	
	if(a==0&&b==0){
		cout<<c*100+a*10+b<<endl;
	}
	else if(a==0){
		cout<<b*100+a*10+c<<endl;
	}
	else{
		cout<<a*100+b*10+c<<endl;
	}
}

Python :

n = int(input())
# a>b>c
a = n // 100;
b = n // 10 % 10;
c = n % 10;
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 c != 0:
    print(c*100+b*10+a)
elif b == 0 and c == 0:
    print(a*100)
elif c == 0:
    print(b*100 + a)