OJ Board

Why am I getting WA? I've compared my outputs to uDebug outputs, and it produces the correct one


#include<iostream>
#include<string>
#include<sstream>
#include<cstdio>
using namespace std;

long change (string text) { //converts string to int
long result;
stringstream convert(text);
if ...

For you guys that get TLE, try this algorithm, it's not very fast, but good enough


You only need to check if, say S is the total sum from 1 to n, then check if S-k is even and larger than -1

For the fastest time, try to find the function f(n) for even n, and for odd n. They have different f(n).