/*
* Author: Geeza
*/
#include <bits/stdc++.h>
#define ld long double
#define ll long long
#define pb push_back
#define fin(a, n) for(int i = a; i < n; i++)
#define fjn(a, n) for(int j = a; j < n; j++)
#define all(a) a.begin(),a.end()
#define allr(a) a.rbegin(),a.rend()
#define FAST ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr)
using namespace std;
const double PI = acos(-1);
const int N = 1e5+5;
const ll oo = 0x3f3f3f3f3f3f3f3f;
const int mod = 1000000007, inf = 1e6;
string di[] = {"D","L", "U", "R", "UL", "UR", "DL", "DR"};
int dx[] = {+1, +0, +0, -1, -1, -1, +1, +1};
int dy[] = {+0, -1, +1, +0, -1, +1, -1, +1};
char dc[] = {'D', 'L', 'R', 'U'};
ll n, k;
vector<ll> v;
map<ll, pair<ll, ll>> mp;
ll dp[205][205];
ll calc(int idx, int rem, ll twos, ll fives) {
if (rem == 0) return 0;
if (idx == n) return -oo;
ll &ret = dp[idx][rem];
if (~ret) return ret;
ret = calc(idx+1, rem, twos, fives);
}
void solve() {
cin >> n >> k;
v.assign(n, 0);
fin(0, n) cin >> v[i];
fin(0, n) {
ll tmp = v[i];
bool good = true;
while (good && tmp > 0) {
if (tmp%2 == 0) {
mp[v[i]].first++;
tmp /= 2;
continue;
}
if (tmp%5 == 0) {
mp[v[i]].second++;
tmp /= 5;
continue;
}
good = false;
}
}
memset(dp, -1, sizeof dp);
cout << calc(0, k, 0, 0) << "\n";
}
int main() {
FAST;
#ifndef ONLINE_JUDGE
freopen("input.txt","r",stdin);
freopen("output.txt","w",stdout);
#endif
int tt = 1; //cin >> tt;
while(tt--){
solve();
}
return 0;
}
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