Submission #233644

#	Time	Username	Problem	Language	Result	Execution time	Memory
233644		triple_fault	Detecting Molecules (IOI16_molecules)	C++14	19 / 100	5 ms	512 KiB

molecules

#include "molecules.h"

using namespace std;

#define ll long long

std::vector<int> find_subset(int l, int u, std::vector<int> w) {
    ll n = (ll)w.size();
    vector<ll> ps(n); ll vals[n];
    for (ll i = 0; i < n; ++i) vals[i] = (ll)w[i];
    ll L = (ll)l, R = (ll)u;

    ps[0] = vals[0];
    for (ll i = 1; i < n; ++i) ps[i] = ps[i - 1] + vals[i];

    for (ll i = 0; i < n; ++i) {
        ll xprev = 0;
        if (i) xprev = ps[i - 1];

        ll xmin = xprev + L, xmax = xprev + R;

        ll lm = n, rm = n;
        ll left = i, right = n - 1;
        while (left <= right) {
            ll mid = (left + right) / 2;
            if (ps[mid] >= xmin) {
                lm = mid;
                right = mid - 1;
            } else left = mid + 1;
        }

        left = i, right = n - 1;
        while (left <= right) {
            ll mid = (left + right) / 2;
            if (ps[mid] >= (xmax + 1)) {
                rm = mid;
                right = mid - 1;
            } else left = mid + 1;
        }

        if (lm < n && (rm - lm) > 0) {
            ll fst = lm, lst = rm - 1;
            vector<int> ret;
            for (ll j = i; j <= fst; ++j) ret.push_back((int)j);
            return ret;
        }
    }
    return vector<int>(0);
}

Compilation message (stderr)

molecules.cpp: In function 'std::vector<int> find_subset(int, int, std::vector<int>)':
molecules.cpp:42:26: warning: unused variable 'lst' [-Wunused-variable]
             ll fst = lm, lst = rm - 1;
                          ^~~

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