A. Stickogon

思路:

Code:

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

void solve() {
    int n; cin >> n;
    map <int, int> mp;
    for (int i = 1, x; i <= n; i++) {
        cin >> x; mp[x] ++;
    }
    int ans = 0;
    for (const pair <int, int> &i : mp) {
        ans += i.second / 3;
    }
    cout << ans << '\n';
}

int main() {
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    int T; cin >> T;
    while (T--) {
        solve();
    }
    return 0;
}

B. A BIT of a Construction

Code:

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

void solve() {
    int n, k, x = 1; cin >> n >> k;
    if (n == 1) {
        cout << k << '\n';
        return ;
    }
    while ((x << 1 | 1) < k) {
        x = x << 1 | 1;
    } 
    cout << x << ' ' << k - x << ' ';
    for (int i = 3; i <= n; i++) cout << 0 << ' ';
    cout << '\n'; 

}

int main() {
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    int T; cin >> T;
    while (T--) {
        solve();
    }
    return 0;
}