#include <iostream>
using namespace std;
void nullify(char ch[]){
for(int i = 0; i < 100; ++i){
    ch[i] = 0;
}
}
int main(){
    char ll[100];
    nullify(ll);
    cin >> ll;
    int match = 0;
    bool f = false;
    for(int i = 0; i < 100; ++i){
        switch(ll[i]){
        case 89:
            match = 1;
        break;
        case 97:
            if(match == 1){
                ++match;
            }else{
                match = 0;
            }
        break;
        case 114:
            if(match == 2){
                ++match;
            }else{
                match = 0;
            }
        break;
        case 100:
            if(match == 3){
                ++match;
            }else{
                match = 0;
            }
        break;
        case 105:
            if(match == 4){
                ++match;
            }else{
                match = 0;
            }
        break;
        default:
            match = 0;
        break;
        }
        if(match == 5){
            f = true;
            break;
        }
    }
    if(f == true){
        cout << "YES";
    }else{
        cout << "NO";
    }
    return 0;
}