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Original proposer: admin

We can receive \(N\) as a string and check if the first, second, and third characters are all equal. To check the equality, one may use an if statement, or sort it and check if the first and the last are equal.
Alternatively, one may solve it by using the property that the answer is Yes if and only if \(111\) divides \(N\).

Sample code in C++ 1:

#include <bits/stdc++.h>
using namespace std;

int main(){
    string N;cin>>N;
    if(N[0]==N[1]&N[1]==N[2]){
        cout<<"Yes"<<"\n";
    }
    else{
        cout<<"No"<<"\n";
    }
}

Sample code in C++ 2:

#include <bits/stdc++.h>
using namespace std;

int main(){
    int N;cin>>N;
    if(N%111==0){
        cout<<"Yes"<<"\n";
    }
    else{
        cout<<"No"<<"\n";
    }
}

Sample code in Python 1:

N=input()
if N[0]==N[1]==N[2]:
    print("Yes")
else:
    print("No")

Sample code in Python 2:

N=sorted(input())
if N[0]==N[2]:
    print("Yes")
else:
    print("No")

Sample code in Python 3:

N=input()
if min(N)==max(N):
    print("Yes")
else:
    print("No")

Sample code in Python 4:

N=int(input())
if N%111==0:
    print("Yes")
else:
    print("No")