Submission #1055538

#	Time	Username	Problem	Language	Result	Execution time	Memory
1055538		Trent	Packing Biscuits (IOI20_biscuits)	C++17	0 / 100	15 ms	604 KiB

biscuits

#include "biscuits.h"
#include "bits/stdc++.h"
using namespace std;
#define forR(i, x) for(int i = 0; i < (x); ++i)
#define REP(i, a, b) for(int i = (a); i < (b); ++i)
#define all(x) x.begin(), x.end()
typedef long long ll;
typedef vector<ll> vll;

ll valOf(ll msk, vll& dc) {
	ll ret = 0;
	forR(i, dc.size()) if(msk & (1 << i)) ret += dc[dc.size() - 1 - i];
	return ret;
}
long long count_tastiness(long long x, std::vector<long long> a) {
	a.insert(a.begin(), (ll) 0);
	int k = a.size();
	vll ftp(k);
	vll sm(k);
	sm[0] = a[0];
	REP(i, 1, k) sm[i] = sm[i-1] + (1 << (i-1)) * a[i];
	forR(i, k) {
		if(i == 0) ftp[i] = 1;
		else {
			cerr << i << ": \n";
			ll st = sm[i];
			vll dc = {(1 << (i-1)) * x};
			ll msk = 0;
			for(int j = i-1; j >= 0; --j) {
				// st - dc(lo) >= sm[j], st - dc(hi) < sm[j]
				if(st - valOf(msk, dc) >= sm[j]) {
					ll lo=msk, hi=(1 << dc.size());
					while(hi - lo > 1) {
						int mid = (lo+hi)/2;
						if(st - valOf(mid, dc) >= sm[j]) lo = mid;
						else hi = mid;
					}
					ftp[i] += (hi - msk) * ftp[j];
					cerr << j << ' ' << hi << ' ' << ftp[i] << '\n';
					if(hi == (1 << dc.size())) break;
					msk = hi << 1;
					dc.push_back((1 << (j-1)) * x);
				}
			}
		}
	}

	vll vals = {sm[k-1]};
	for(int i = k - 1; i > 0; --i) {
		vll nex;
		for(ll j : vals) {
			j = min(j, sm[i]);
			nex.push_back(j);
			if(j - (1 << (i-1)) * x >= 0) nex.push_back(j - (1 << (i-1)) * x);
		}
		vals.swap(nex);
	}

	forR(i, k) cerr << sm[i] << ' ';
	cerr << '\n';
	forR(i, k) cerr << ftp[i] << ' ';
	cerr << '\n';
	assert(ftp[k-1] == vals.size());
	return vals.size();
}

Compilation message (stderr)

biscuits.cpp: In function 'll valOf(ll, vll&)':
biscuits.cpp:4:37: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    4 | #define forR(i, x) for(int i = 0; i < (x); ++i)
      |                                     ^
biscuits.cpp:12:2: note: in expansion of macro 'forR'
   12 |  forR(i, dc.size()) if(msk & (1 << i)) ret += dc[dc.size() - 1 - i];
      |  ^~~~
In file included from /usr/include/c++/10/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:33,
                 from biscuits.cpp:2:
biscuits.cpp: In function 'long long int count_tastiness(long long int, std::vector<long long int>)':
biscuits.cpp:63:18: warning: comparison of integer expressions of different signedness: '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   63 |  assert(ftp[k-1] == vals.size());

• Subtask 1: 0 / 9
• Subtask 2: 0 / 12
• Subtask 3: 0 / 21
• Subtask 4: 0 / 35
• Subtask 5: 0 / 23