Submission #1118299

#	Time	Username	Problem	Language	Result	Execution time	Memory
1118299		crafticat	Detecting Molecules (IOI16_molecules)	C++17	9 / 100	1 ms	504 KiB

molecules

#include <bits/stdc++.h>
#include "molecules.h"


using namespace std;

template<typename T>
using V = vector<T>;
using ll = long long;
using vi = V<int>;
using pi = pair<int,int>;
constexpr int INF = 1e9 + 7;

#define F0R(i, n) for (int i = 0; i < n;i++)
#define FOR(i, j , n) for (int i = j ;i < n;i++)

vi possible(ll l, ll u, V<ll> w, int k) {
    int ptrEnd = w.size() - k; //including
    int ptrStart = 0; // Not including

    ll curSum = 0;
    FOR(i, ptrEnd, w.size())
        curSum += w[i];

    while (curSum > u && ptrStart < k) {
        curSum -= w[ptrEnd]; ptrEnd++;
        curSum += w[ptrStart]; ptrStart++;
    }

    if (curSum <= u && curSum >= l) {
        vi vals;
        ll newSum = 0;
        F0R(i, ptrStart) {
            vals.push_back(i);
            newSum += w[i];
        }
        FOR(i, ptrEnd, w.size()) {
            vals.push_back(i);
            newSum += w[i];
        }
        if (newSum != curSum or vals.size() != k) exit(5);
        return vals;
    }
    return {};
}

std::vector<int> find_subset(int l2, int u2, std::vector<int> w2) {
    ll l = l2, u = u2;
    V<ll> w(w2.size());
    F0R(i, w.size()) w[i] = w2[i];

    sort(w.begin(), w.end());
    ll offset = w[0];

    for (auto &x : w)
        x -= offset;

    V<ll> prefixSums(w.size() + 1), revPrefixSums(w.size() + 1); // Not including, including
    F0R(i, w.size()) {
        prefixSums[i + 1] = prefixSums[i] + w[i];
    }
    F0R(i, w.size()) {
        prefixSums[i] = prefixSums[i + 1] + w[i];
    }

    FOR(k, 1, w.size() + 1) {
        auto r = possible(l - k * offset, u - k * offset, w, k);
        if (!r.empty()) return r;
    }
    return {};
}

#if DEBUG

int main() {
    int n, l, u;
    assert(3 == scanf("%d %d %d", &n, &l, &u));
    std::vector<int> w(n);
    for (int i = 0; i < n; i++)
        assert(1 == scanf("%d", &w[i]));
    std::vector<int> result = find_subset(l, u, w);

    printf("%d\n", (int)result.size());
    for (int i = 0; i < (int)result.size(); i++)
        printf("%d%c", result[i], " \n"[i == (int)result.size() - 1]);
}
#endif

Compilation message (stderr)

molecules.cpp: In function 'vi possible(ll, ll, V<long long int>, int)':
molecules.cpp:15:41: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int, std::allocator<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 | #define FOR(i, j , n) for (int i = j ;i < n;i++)
......
   22 |     FOR(i, ptrEnd, w.size())
      |         ~~~~~~~~~~~~~~~~~~~              
molecules.cpp:22:5: note: in expansion of macro 'FOR'
   22 |     FOR(i, ptrEnd, w.size())
      |     ^~~
molecules.cpp:15:41: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int, std::allocator<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 | #define FOR(i, j , n) for (int i = j ;i < n;i++)
......
   37 |         FOR(i, ptrEnd, w.size()) {
      |             ~~~~~~~~~~~~~~~~~~~          
molecules.cpp:37:9: note: in expansion of macro 'FOR'
   37 |         FOR(i, ptrEnd, w.size()) {
      |         ^~~
molecules.cpp:41:45: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   41 |         if (newSum != curSum or vals.size() != k) exit(5);
      |                                 ~~~~~~~~~~~~^~~~
molecules.cpp: In function 'std::vector<int> find_subset(int, int, std::vector<int>)':
molecules.cpp:14:37: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int, std::allocator<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 | #define F0R(i, n) for (int i = 0; i < n;i++)
......
   50 |     F0R(i, w.size()) w[i] = w2[i];
      |         ~~~~~~~~~~~                  
molecules.cpp:50:5: note: in expansion of macro 'F0R'
   50 |     F0R(i, w.size()) w[i] = w2[i];
      |     ^~~
molecules.cpp:14:37: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int, std::allocator<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 | #define F0R(i, n) for (int i = 0; i < n;i++)
......
   59 |     F0R(i, w.size()) {
      |         ~~~~~~~~~~~                  
molecules.cpp:59:5: note: in expansion of macro 'F0R'
   59 |     F0R(i, w.size()) {
      |     ^~~
molecules.cpp:14:37: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int, std::allocator<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 | #define F0R(i, n) for (int i = 0; i < n;i++)
......
   62 |     F0R(i, w.size()) {
      |         ~~~~~~~~~~~                  
molecules.cpp:62:5: note: in expansion of macro 'F0R'
   62 |     F0R(i, w.size()) {
      |     ^~~
molecules.cpp:15:41: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int, std::allocator<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 | #define FOR(i, j , n) for (int i = j ;i < n;i++)
......
   66 |     FOR(k, 1, w.size() + 1) {
      |         ~~~~~~~~~~~~~~~~~~               
molecules.cpp:66:5: note: in expansion of macro 'FOR'
   66 |     FOR(k, 1, w.size() + 1) {
      |     ^~~

• Subtask 1: 9 / 9
• Subtask 2: 0 / 10
• Subtask 3: 0 / 12
• Subtask 4: 0 / 15
• Subtask 5: 0 / 23
• Subtask 6: 0 / 31