#include <bits/stdc++.h>
#define ll long long

using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    string S;
    cin >> S;
    for(int i=0; i<S.length(); i+=2) { if(isupper(S[i])) { cout << "No"; return 0; } }
    for(int i=1; i<S.length(); i+=2) { if(islower(S[i])) { cout << "No"; return 0; } }
    cout << "Yes";

    return 0;
}

#include<iostream>
using namespace std;
int main()
{
    int n;
    cin >> n;
    cout << n-1;
}