C :

#include<stdio.h>
int main(){
	int a,b,c;
	scanf("%d %d %d",&a,&b,&c);
	if(a+b>c){
		printf("%s","yes");
	}else{
		printf("%s","no");
	}
	return 0;
}

C++ :

#include<iostream>
using namespace std;
int main(){
	int a,b,c;
	cin>>a>>b>>c;
	if(a+b>c&&a+c>b&&c+b>c){
		cout<<"yes"<<endl;
		
	}else{
		cout<<"no"<<endl;
	}
}

Python :

a,b,c = map(int, input().split() ) 
if a+b>c:
    print('yes')
else:
    print('no')