https://www.acmicpc.net/problem/13985 13985번: Equality Print, on a single line, YES if the sum is correct; otherwise, print NO. www.acmicpc.net 문제 You are grading an arithmetic quiz. The quiz asks a student for the sum of the numbers. Determine if the student taking the quiz got the question correct. 입력 The first and the only line of input contains a string of the form: a + b = c It is guarantee..