CCCPaste

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#include 
#include 
#include 
#include 
#include 
#include 
#include 
using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    string n;
    cin >> n;
    int F = (n[0] - '0');
    int S = (n[1] - '0');
    int T = (n[2] - '0');
    
    for(int i = 0; i < 1000; i++) {
        int tmp = T;
        T = (T + S + F) % 10;
        F = S;
        S = tmp;
        n += (T + '0');
        int sz = (int) n.size();
        if(n[0] == n[sz - 3] and n[1] == n[sz - 2] and n[2] == n[sz - 1]) {
            n.erase(n.end() - 1);
            n.erase(n.end() - 1);
            n.erase(n.end() - 1);
            break;
        }
    }
    long long K;
    cin >> K;
    K %= n.size();
    if(K == 0) {
        cout << n[n.size() - 1] << endl;
    }
    else {
        cout << n[K - 1] << endl;
    }

    return 0;
}
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