Codeforces 697A.Pineapple Incident

278

题目


Description


Ted has a pineapple. This pineapple is able to bark like a bulldog! At time t (in seconds) it barks for the first time. Then every s seconds after it, it barks twice with 1 second interval. Thus it barks at times t, t + s, t + s + 1, t + 2s, t + 2s + 1, etc.


Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time x (in seconds), so he asked you to tell him if it's gonna bark at that time.



Input  


The first and only line of input contains three integers t, s and x (0 ≤ t, x ≤ 109, 2 ≤ s ≤ 109) — the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively.


Output  


Print a single "YES" (without quotes) if the pineapple will bark at time x or a single "NO" (without quotes) otherwise in the only line of output.

Examples



input  


3 10 4

output  


NO

input  


3 10 3

output  


YES

input  


3 8 51

output  


YES

input  


3 8 52

output  


YES


Note  


In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3.

In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52.


题解


遍历一下会不会在 x 的时候叫即可

代码


/*
By:OhYee
Github:OhYee
Blog:http://www.oyohyee.com/
Email:oyohyee@oyohyee.com

かしこいかわいい?
エリーチカ!
要写出来Хорошо的代码哦~
*/
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <cmath>
#include <string>
#include <iostream>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <functional>
using namespace std;

const int maxn = 35;

bool Do() {
int t,s,x;
if(scanf("%d%d%d",&t,&s,&x) == EOF)
return false;

bool flag = true;
for(int i = 0;;i++) {
int time = t + i*s;
if(x == time) {
printf("YES\n");
break;
}

if(i != 0) {
int time = t + i*s + 1;
if(x == time) {
printf("YES\n");
break;
}
}

if(x < time) {
printf("NO\n");
break;
}
}

return true;
}

int main() {
while(Do());
return 0;
}
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