C :

#include<stdio.h>
int main(){
	int a,b,c;
	scanf("%d%d%d",&a,&b,&c);
	if(a>=b&&a>=c){
		printf("%d",a);	
	}
	if(b>=a&&b>=c){
		printf("%d",b);	
	}
	if(c>=b&&c>=a){
		printf("%d",c);	
	}	
}

C++ :

#include<iostream>
#include<iomanip>
using namespace std;
int main(){
	int a,b,c;
	cin>>a>>b>>c;
	if(a>b&&a>c){
		cout<<a<<endl;
	}else if(b>c){
		cout<<b<<endl;
	}else{
		cout<<c<<endl;
	}
	
}
	

Python :

a,b,c = map(int,input().split());
t = a
if t < b:
    t = b;

if t < c:
    t = c;

print(t)