# code:
```cpp
#include <bits/stdc++.h>
using namespace std;
int main(){
double v = 7,f = 0,s,x,a = 0;
cin >> s >> x;
if(s - x <= 0 && s + x >= v){
cout << 'y';
return 0;
}
while(a <= s+x){
a += v;
v *= 0.98;
if(a >= s - x && a <= s + x){
if(a + v <= s + x){
cout << 'y';
return 0;
}else if(a + v > s + x){
cout << 'n';
return 0;
}
}
}
return 0;
}
```
by lihaoyu68 @ 2024-04-23 17:40:21