Submission #304831

#	Time	Username	Problem	Language	Result	Execution time	Memory
304831		2qbingxuan	Packing Biscuits (IOI20_biscuits)	C++14	100 / 100	347 ms	1528 KiB

biscuits

#include <bits/stdc++.h>
#ifdef local
#define safe std::cerr<<__PRETTY_FUNCTION__<<" line "<<__LINE__<<" safe\n"
#define debug(...) qqbx(#__VA_ARGS__, __VA_ARGS__)
template <typename H, typename ...T> void qqbx(const char*s, const H &h, T ...args) {
    for(; *s && *s != ','; ++s) if(*s != ' ') std::cerr << *s;
    std::cerr << " = " << h << (sizeof...(T) ? ", " : "\n");
    if constexpr (sizeof...(T)) qqbx(++s, args...);
}
#else
#include "biscuits.h"
#define debug(...) ((void)0)
#define safe ((void)0)
#endif // local
#define pb emplace_back

using namespace std;
typedef long long ll;
const int N = 2500025;

ll count_tastiness(ll x, vector<ll> a) {
    int k = a.size();
    cerr << x << '\n';
    for(int i = 0; i < k; i++) cerr << a[i] << (i+1==k ? '\n' : ' ');
    vector<ll> sum(k);
    sum[0] = a[0];
    for(int i = 1; i < k; i++) sum[i] = sum[i-1] + (a[i] << i);
    for(int i = 0; i < k; i++) sum[i] /= x;
    /* for(int i = 0; i < k; i++) sum[i] = min(sum[i], ((1LL<<i+1)-1)); */
#if 0
    int ans = 0;
    for(int y = 0; y <= sum[k-1]; y++) {
        bool ok = 1;
        int yf = 0;
        for(int i = 0; i < k; i++) {
            yf += y & (1LL << i);
            if(yf > sum[i]) ok = 0;
        }
        if(ok) ++ans;
    }
#else
    k = 60;
    sum.resize(k, sum.back());
    vector<map<ll,ll>> mp(k);
    // count how many y, \forall i, (y & (11...11)) <= lim
    function<ll(int,ll)> calc = [&](int i, ll lim) -> ll {
        if(lim < 0) return 0;
        if(lim > sum[i]) lim = sum[i];
        if(lim > ((1LL<<i+1)-1)) lim = ((1LL<<i+1)-1);
        if(i == 0) return lim + 1;
        if(mp[i].count(lim)) return mp[i][lim];
        if(lim >= (1LL>>i))
            return mp[i][lim] = calc(i-1, lim-(1LL<<i)) + calc(i-1, lim);
        return mp[i][lim] = calc(i-1, lim);
    };
    ll ans = calc(k-1, sum[k-1]);
#endif // 0
    debug(ans);
    return ans;
}

#ifdef local
signed main() {
    count_tastiness(3, {5, 2, 1});
    count_tastiness(2, {2, 1, 2});
    count_tastiness(1, {0, 2});
}
#endif // local

Compilation message (stderr)

biscuits.cpp: In lambda function:
biscuits.cpp:49:26: warning: suggest parentheses around '+' inside '<<' [-Wparentheses]
   49 |         if(lim > ((1LL<<i+1)-1)) lim = ((1LL<<i+1)-1);
      |                         ~^~
biscuits.cpp:49:48: warning: suggest parentheses around '+' inside '<<' [-Wparentheses]
   49 |         if(lim > ((1LL<<i+1)-1)) lim = ((1LL<<i+1)-1);
      |                                               ~^~

• Subtask 1: 9 / 9
• Subtask 2: 12 / 12
• Subtask 3: 21 / 21
• Subtask 4: 35 / 35
• Subtask 5: 23 / 23