Given four integers, two of them add up to the same as the other two X68995
Write a program that reads four integers and determines if the sum of two of them equals the sum of the other two.
Input
Four integers in a line.
Output
If two integers of the four add up to the same sum as the other two,
the output will be YES followed by a newline
character. Otherwise the output is NO followed
by a newline character.
Observation
You cannot use massive storage data structures, such as
string or
vector.
Public test cases
Input
1 2 3 4
Output
YES
Input
-1 -2 -3 -4
Output
YES
Input
8 7 1 6
Output
NO
Input
7 8 7 7
Output
NO
Input
2 8 1 9
Output
YES
Input
1 6 9 4
Output
YES