Cod sursa(job #3303422)

Utilizator raulthestormIlie Raul Ionut raulthestorm Data 15 iulie 2025 15:28:30
Problema Cifra Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 0.77 kb
#include <fstream>

using namespace std;

int ans[100]; /// ans[i] = uc(1^1 + 2^2 + ... + i^i)
string s;

ifstream f("cifra.in");
ofstream g("cifra.out");

int ucif(int n) ///ultima cifra a lui n^n
{
    int uc = n % 10, r = n % 4, p = 1;
    if(r == 0)
        r = 4;
    while(r--)
        p = p * uc;
    return p % 10;
}

void precalc()
{
    for(int i = 1; i < 100; i++)
        ans[i] = (ans[i - 1] + ucif(i)) % 10;
}

void solve()
{
    f >> s;
    int n = s.size(), x;
    if(n == 1)
        x = s[0] - '0';
    else
        x = (s[n - 2] - '0') * 10 + (s[n - 1] - '0');
    g << ans[x] << '\n';
}

int main()
{
    precalc();
    int T;
    f >> T;
    while(T--)
        solve();
    f.close();
    g.close();
    return 0;
}