Submission #828009

#	Time	Username	Problem	Language	Result	Execution time	Memory
828009		minhcool	Packing Biscuits (IOI20_biscuits)	C++17	9 / 100	8 ms	1492 KiB

biscuits

//#define local
#ifndef local
#include "biscuits.h"
#endif
#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;
 
#define int long long
#define fi first
#define se second
#define pb push_back
#define mp make_pair
 
typedef pair<int, int> ii;
typedef pair<ii, int> iii;
typedef pair<ii, ii> iiii;
 
const int N = 3e5 + 5;
 
const int oo = 1e18 + 7, mod = 1e9 + 7;
 
mt19937 rng(1);
 
int rnd(int l, int r){
	int temp = rng() % (r - l + 1);
	return abs(temp) + l;
}
 
int dp[121][20005], expected[121];
 
long long count_tastiness(long long x, std::vector<long long> a) {
	//int n, a[N];
	int sum = 0;
	for(int i = 0; i < a.size(); i++) sum += a[i] * (1LL << i);
	if(sum <= 1e5){
		int answer = 1;
		for(int i = 1; i <= sum/x; i++){
			int rem = 0;
			for(int j = 0; j < a.size(); j++){
				rem += a[j];
				if((i & (1LL << j))) rem -= x;
				if(rem < 0) break;
				rem /= 2;
			}
			//if(rem >= 0) cout << answer << "\n";
			answer += (rem >= 0);
		}
		return answer;
	}
	else if(x <= 1e4){
		//cout << "OK\n";
		for(int i = 0; i <= 20000; i++){
			for(int j = 0; j <= 122; j++) dp[j][i] = 0;
		}
		expected[0] = a[0];
		for(int i = 1; i < a.size() + 62; i++) expected[i] = (expected[i - 1] / 2) + (i < a.size() ? a[i] : 0);
		dp[0][0] = 1;
		if(a[0] >= x) dp[0][x] = 1;
		for(int i = 0; (i + 1) < a.size() + 62; i++){
			for(int j = 0; j <= 20000; j++){
				//if(dp[i][j]) cout << i << " " << j << " " << dp[i][j] << "\n";
				int nxt = ((expected[i] - j) / 2) + ((i + 1) < a.size() ? a[i + 1] : 0), actual = expected[i + 1] - nxt;
				dp[i + 1][actual] += dp[i][j];
				if(nxt >= x){
					nxt -= x, actual += x;
					dp[i + 1][actual] += dp[i][j];
				}
			}
		}
		int answer = 0;
		for(int j = 0; j <= 20000; j++) answer += dp[a.size() + 61][j];
		return answer;
	}
	return 0;
}

Compilation message (stderr)

biscuits.cpp: In function 'long long int count_tastiness(long long int, std::vector<long long int>)':
biscuits.cpp:36:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |  for(int i = 0; i < a.size(); i++) sum += a[i] * (1LL << i);
      |                 ~~^~~~~~~~~~
biscuits.cpp:41:21: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |    for(int j = 0; j < a.size(); j++){
      |                   ~~^~~~~~~~~~
biscuits.cpp:58:20: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |   for(int i = 1; i < a.size() + 62; i++) expected[i] = (expected[i - 1] / 2) + (i < a.size() ? a[i] : 0);
      |                  ~~^~~~~~~~~~~~~~~
biscuits.cpp:58:83: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |   for(int i = 1; i < a.size() + 62; i++) expected[i] = (expected[i - 1] / 2) + (i < a.size() ? a[i] : 0);
      |                                                                                 ~~^~~~~~~~~~
biscuits.cpp:61:26: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   61 |   for(int i = 0; (i + 1) < a.size() + 62; i++){
      |                  ~~~~~~~~^~~~~~~~~~~~~~~
biscuits.cpp:64:50: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   64 |     int nxt = ((expected[i] - j) / 2) + ((i + 1) < a.size() ? a[i + 1] : 0), actual = expected[i + 1] - nxt;
      |                                          ~~~~~~~~^~~~~~~~~~
biscuits.cpp:55:43: warning: iteration 121 invokes undefined behavior [-Waggressive-loop-optimizations]
   55 |    for(int j = 0; j <= 122; j++) dp[j][i] = 0;
      |                                  ~~~~~~~~~^~~
biscuits.cpp:55:21: note: within this loop
   55 |    for(int j = 0; j <= 122; j++) dp[j][i] = 0;
      |                   ~~^~~~~~

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