#416 Div.2 A. Vladik and Courtesy-water

A. Vladik and Courtesy
time limit per test2 seconds
memory limit per test256 megabytes
inputstandard input
outputstandard output
At regular competition Vladik and Valera won a and b candies respectively. Vladik offered 1 his candy to Valera. After that Valera gave Vladik 2 his candies, so that no one thought that he was less generous. Vladik for same reason gave 3 candies to Valera in next turn.

More formally, the guys take turns giving each other one candy more than they received in the previous turn.

This continued until the moment when one of them couldn’t give the right amount of candy. Candies, which guys got from each other, they don’t consider as their own. You need to know, who is the first who can’t give the right amount of candy.

Input
Single line of input data contains two space-separated integers a, b (1 ≤ a, b ≤ 109) — number of Vladik and Valera candies respectively.

Output
Pring a single line “Vladik’’ in case, if Vladik first who can’t give right amount of candy, or “Valera’’ otherwise.

Examples
input
1 1
output
Valera
input
7 6
output
Vladik

大意：
两个人互相给对方 candy 。A 给 B 一个 candy ，B 再给 A 2 个 candy ，A 再给 B 3 个…依次递增。

#include <iostream>#include<cstdio>using namespace std;typedef long long ll;#define D(v) cout<<#v<<" "<<v<<endl#define inf 0x3f3f3f3fint main(){    int a,b;    scanf("%d%d",&a,&b);    int cnt=1;    while(a>=0&&b>=0){        a-=cnt;        cnt++;        b-=cnt;        cnt++;    }    if(a>=0) puts("Valera");    else puts("Vladik");    return 0;}