#include <iostream> #include <vector> #include <algorithm> using namespace std; int main() { int n; cin >> n; int sum = 0; vector<int> dp(10, n); dp[0] = 0; for (int i = 0; i < n; i++) { int a; cin >> a; sum += a, sum %= 10; vector<int> after(10, n); for (int j = 0; j < 10; j++) { after[(j + a) % 10] = min(dp[(j + a) % 10], dp[j] + 1); } dp = after; } cout << n - dp[sum] << endl; return 0; }