Submission #50756

#	Time	Username	Problem	Language	Result	Execution time	Memory
50756		Mamnoon_Siam	Detecting Molecules (IOI16_molecules)	C++17	100 / 100	128 ms	28576 KiB

molecules

#pragma GCC optimize("Ofast,unroll-loops,no-stack-protector")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include "molecules.h"
#include <bits/stdc++.h>
using namespace std;

#define debug(s) cout<< #s <<" = "<< s <<endl
#define all(v) (v).begin(), (v).end()
#define KeepUnique(v) (v).erase( unique(all(v)), v.end() )
#define MEMSET(a,val) memset(a, val, sizeof a)
#define PB push_back
#define endl '\n'
typedef long long ll;

inline int myrand(int l, int r) {
	int ret = rand(); ret <<= 15; ret ^= rand();
	if(ret < 0) ret = -ret; ret %= (r-l+1); ret += l;
	return ret;
}
template <typename F, typename S>
ostream& operator << (ostream& os, const pair< F, S>& p) {
    return os<<"(" <<p.first<<", "<<p.second<<")"; }

typedef pair<int, int> ii;
template<typename T> using min_pq =
	priority_queue<T, vector<T>, greater<T> >;

//int dx[] = {-1, +0, +1, +0};
//int dy[] = {+0, +1, +0, -1};

vector<ll> a, idx;
ll l, r;

vector<int> get_prefix(int k) {
	vector<int> ret;
	for(int i = 0; i < k; i++) {
		ret.push_back(idx[i]);
	} return ret;
}
vector<int> get_suffix(int k) {
	vector<int> ret;
	for(int i = 0, j = a.size() - 1; i < k; i++, j--) {
		ret.push_back(idx[j]);
	} return ret;
}
vector<int> subarray(int x, int y) {
	vector<int> ret;
	for(int i = x; i <= y; i++) {
		ret.push_back(idx[i]);
	} return ret;
}

vector<int> get_whole(int k) {
	ll s = 0;
	for(int i = 0; i < k; i++)
		s += a[i];
	int lp = 0, rp = k - 1;
	while(true) {
		s -= a[lp++];
		s += a[++rp];
		if(l <= s and s <= r) {
			return subarray(lp, rp);
		}
	}
}

vector<int> find_subset(int L, int R, vector<int> w) {
	l = L, r = R;
    for(int i = 0; i < w.size(); i++) {
    	idx.push_back(i);
    	a.push_back(w[i]);
    }
    sort(all(idx), [](int x, int y){return a[x] < a[y];});
    sort(all(a));
    ll pre = 0, suf = 0;
    for(int i = 1; i <= a.size(); i++) {
    	pre += a[i - 1], suf += a[a.size() - i];
    	if(l <= pre and pre <= r) return get_prefix(i);
    	if(l <= suf and suf <= r) return get_suffix(i);
    	if(pre < l and r < suf) return get_whole(i);
    }
    return vector<int>();
}

Compilation message (stderr)

molecules.cpp: In function 'int myrand(int, int)':
molecules.cpp:18:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if(ret < 0) ret = -ret; ret %= (r-l+1); ret += l;
  ^~
molecules.cpp:18:26: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
  if(ret < 0) ret = -ret; ret %= (r-l+1); ret += l;
                          ^~~
molecules.cpp: In function 'std::vector<int> find_subset(int, int, std::vector<int>)':
molecules.cpp:70:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < w.size(); i++) {
                    ~~^~~~~~~~~~
molecules.cpp:77:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 1; i <= a.size(); i++) {
                    ~~^~~~~~~~~~~

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