Submission #736157

#	Time	Username	Problem	Language	Result	Execution time	Memory
736157		marvinthang	Index (COCI21_index)	C++17	110 / 110	1460 ms	143008 KiB

index

/******************************
*    author : @marvinthang    *
*    date : 10 / 02 / 2022    *
******************************/

#include <bits/stdc++.h>

using namespace std;

#define  superspeed  ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
#define  file(name)  if (fopen (name".inp", "r")) { freopen (name".inp", "r", stdin); freopen (name".out", "w", stdout); }

template <class U, class V> ostream & operator << (ostream& out, const pair<U, V> &p) { return out << '(' << p.first << ", " << p.second << ')'; }
template <class T> ostream & operator << (ostream &out, const vector<T> &vt) { out << '{'; for (size_t i = 0; i + 1 < vt.size(); i++) out << vt[i] << ", "; if (!vt.empty()) out << vt.back(); return out << '}'; }

const 		int MOD = 1e9 + 7;
const     double PI = 3.1415926535897932384626433832795; // acos(-1.0); atan(-1.0);
const     int dir[] = {0, 1, 0, -1, 0}; // {0, 1, 1, -1, -1, 1, 0, -1, 0};
const       int MAX = 2e5 + 5;

struct Node {

	Node *l, *r;
	int val;

	Node(Node *_l = nullptr, Node *_r = nullptr, int v = 0) {
		l = _l; r = _r; val = v;
	}

};

Node *versions[MAX];
const int oo = 1 << 18;

void build(Node *cur, int l = 1, int r = oo - 1) {
	if (l == r) return;
	int mid = l + r >> 1;
	cur -> l = new Node();
	build(cur -> l, l, mid);
	cur -> r = new Node();
	build(cur -> r, mid + 1, r);
}

void upgrade(Node *prev, Node *cur, int pos, int val, int l = 1, int r = oo - 1) {
	if (l > pos || r < pos) return;
	if (l == r) {
		cur -> val = prev -> val + val;
		return;
	}
	int mid = l + r >> 1;
	if (pos <= mid) {
		cur -> r = prev -> r;
		cur -> l = new Node();
		upgrade(prev -> l, cur -> l, pos, val, l, mid);
	} else {
		cur -> l = prev -> l;
		cur -> r = new Node();
		upgrade(prev -> r, cur -> r, pos, val, mid + 1, r);
	}
	cur -> val = cur -> l -> val + cur -> r -> val;
}

int get(Node *prev, Node *cur, int u, int l = 1, int r = oo - 1) {
	if (l > oo || r < u) return 0;
	if (u <= l) return cur -> val - prev -> val;
	int mid = l + r >> 1;
	return get(prev -> l, cur -> l, u, l, mid) + get(prev -> r, cur -> r, u, mid + 1, r);
}

int N, Q, A[MAX];

int main(void) {
    superspeed;
    file("coci2021_r6_index");
    scanf("%d%d", &N, &Q);
    for (int i = 1; i <= N; ++i) scanf("%d", A + i);
    versions[0] = new Node();
    build(versions[0]);
	for (int i = 1; i <= N; ++i) {
		versions[i] = new Node();
		upgrade(versions[i - 1], versions[i], A[i], 1);
	}
    while (Q--) {
    	int l, r; scanf("%d%d", &l, &r);
    	int low = 1, high = oo;
    	while (low <= high) {
    		int mid = low + high >> 1;
    		if (get(versions[l - 1], versions[r], mid) >= mid)
    			low = mid + 1;
    		else high = mid - 1;
    	}
    	printf("%d\n", high);
    }
    return 0;
}

Compilation message (stderr)

index.cpp: In function 'void build(Node*, int, int)':
index.cpp:37:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   37 |  int mid = l + r >> 1;
      |            ~~^~~
index.cpp: In function 'void upgrade(Node*, Node*, int, int, int, int)':
index.cpp:50:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   50 |  int mid = l + r >> 1;
      |            ~~^~~
index.cpp: In function 'int get(Node*, Node*, int, int, int)':
index.cpp:66:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   66 |  int mid = l + r >> 1;
      |            ~~^~~
index.cpp: In function 'int main()':
index.cpp:87:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   87 |       int mid = low + high >> 1;
      |                 ~~~~^~~~~~
index.cpp:11:61: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 | #define  file(name)  if (fopen (name".inp", "r")) { freopen (name".inp", "r", stdin); freopen (name".out", "w", stdout); }
      |                                                     ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
index.cpp:74:5: note: in expansion of macro 'file'
   74 |     file("coci2021_r6_index");
      |     ^~~~
index.cpp:11:95: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 | #define  file(name)  if (fopen (name".inp", "r")) { freopen (name".inp", "r", stdin); freopen (name".out", "w", stdout); }
      |                                                                                       ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
index.cpp:74:5: note: in expansion of macro 'file'
   74 |     file("coci2021_r6_index");
      |     ^~~~
index.cpp:75:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   75 |     scanf("%d%d", &N, &Q);
      |     ~~~~~^~~~~~~~~~~~~~~~
index.cpp:76:39: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   76 |     for (int i = 1; i <= N; ++i) scanf("%d", A + i);
      |                                  ~~~~~^~~~~~~~~~~~~
index.cpp:84:21: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   84 |      int l, r; scanf("%d%d", &l, &r);
      |                ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 40 / 40
• Subtask 3: 50 / 50