#include<stdio.h>
int main() {
unsigned int a;
float taxi;
scanf("%d", &a);
taxi = a / 10.0 + 10; //计算打车时间
printf("%c", a < taxi ? 'w' : 'v'); //判断走路时间是否小于打车时间,是输出w,否输出v
return 0;
}