Submission #2216620

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Source Code Expand

#include <algorithm>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <deque>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <utility>
#include <vector>
#define p(s) cout<<(s)<<endl
#define REP(i,n,N) for(int i=n;i<N;i++)
#define RREP(i,n,N) for(int i=N-1;i>=n;i--)
#define CK(n,a,b) ((a)<=(n)&&(n)<(b))
#define F first
#define S second
typedef long long ll;
using namespace std;
const int inf = 1e9;

string s,t;
int main(){
    cin>>s;
    t=s;
    string ans = "YES";
    RREP(i,4,t.size()+1){
        if(i>=5&&(t.substr(i-5,5)=="dream"||t.substr(i-5,5)=="erase")){
            i-=4;
        }
        else if(i>=7&&t.substr(i-7,7)=="dreamer"){
            i-=6;
        }else if(i>=6&&t.substr(i-6,6)=="eraser"){
            i-=5;
        }else{
            ans="NO";
            break;
        }
    }
    p(ans);
    return 0;
}

Submission Info

Judge Result