#!/usr/bin/python3
a,b,c=map(int,input().split())

if a+b>c and a+c>b and c+b>a:
    print("Yes")
else:
    print("No")

/**************************************************************
	Problem: 1045
	User: admin
	Language: Python
	Result: Accepted
	Time:92 ms
	Memory:34244 kb
****************************************************************/