Cod sursa(job #2562576)

Utilizator radustn92Radu Stancu radustn92 Data 29 februarie 2020 15:41:29
Problema Nums Scor 15
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 4.04 kb
#include <cstdio>
#include <cstdlib>
#include <ctime>
#include <algorithm>
#include <string>
#include <vector>
#include <fstream>
using namespace std;

ifstream in("nums.in");
ofstream out("nums.out");

struct query {
	int opType;
	int key;
	string s;
	int K;
};
vector<query> queries;
vector<pair<int, string>> strings;
int totalOps;

struct node {
	int key;
	int priority;
	int size;

	node* leftChild;
	node* rightChild;

	node() {}

	node(int _key) {
		key = _key;
		priority = rand();
		leftChild = rightChild = NULL;
	}
};
typedef node* pnode;

int getSize(pnode node) {
	if (node == NULL) {
		return 0;
	}
	return 1 + getSize(node -> leftChild) + getSize(node -> rightChild);
}

void updateSize(pnode node) {
	if (node != NULL) {
		node -> size = getSize(node);
	}
}

pair<pnode, pnode> split(pnode root, int key) {
	if (root == NULL) {
		return {NULL, NULL};
	}
	if (key < root -> key) {
		pair<pnode, pnode> leftSplit = split(root -> leftChild, key);
		root -> leftChild = leftSplit.second;
		updateSize(root);
		return {leftSplit.first, root};
	}
	pair<pnode, pnode> rightSplit = split(root -> rightChild, key);
	root -> rightChild = rightSplit.first;
	updateSize(root);
	return {root, rightSplit.second};
}

pnode merge(pnode leftTree, pnode rightTree) {
	if (leftTree == NULL || rightTree == NULL) {
		return (leftTree == NULL) ? rightTree : leftTree;
	}

	if (leftTree -> priority > rightTree -> priority) {
		leftTree -> rightChild = merge(leftTree -> rightChild, rightTree);
		updateSize(leftTree);
		return leftTree;
	}
	rightTree -> leftChild = merge(leftTree, rightTree -> leftChild);
	updateSize(rightTree);
	return rightTree;
}

pnode search(pnode root, int key) {
	if (root == NULL || root -> key == key) {
		return root;
	}
	if (key < root -> key) {
		return search(root -> leftChild, key);
	}
	return search(root -> rightChild, key);
}

pnode insert(pnode root, pnode toInsert) {
	if (root == NULL) {
		return toInsert;
	}
	if (toInsert -> priority > root -> priority) {
		pair<pnode, pnode> splitByInsertionKey = split(root, toInsert -> key);
		toInsert -> leftChild = splitByInsertionKey.first;
		toInsert -> rightChild = splitByInsertionKey.second;
		updateSize(toInsert);
		return toInsert;
	}
	if (toInsert -> key < root -> key) {
		root -> leftChild = insert(root -> leftChild, toInsert);
	} else {
		root -> rightChild = insert(root -> rightChild, toInsert);
	}
	updateSize(root);
	return root;
}

pnode insert(pnode root, int key) {
	pnode prevNode = search(root, key);
	if (prevNode == NULL) {
		root = insert(root, new node(key));
	}
	return root;
}

pnode findKth(pnode root, int K) {
	if (root == NULL) {
		return NULL;
	}

	int currNodeIdx = getSize(root -> leftChild) + 1;
	if (K == currNodeIdx) {
		return root;
	} else if (K < currNodeIdx) {
		return findKth(root -> leftChild, K);
	}
	return findKth(root -> rightChild, K - currNodeIdx);
}

void debug(pnode root) {
	if (root == NULL) {
		return;
	}
	debug(root -> leftChild);
	out << strings[root -> key].second << " ";
	debug(root -> rightChild);
}

void preProcessQueries() {
	in >> totalOps;
	strings.reserve(totalOps);
	queries.reserve(totalOps);
	for (int opIdx = 0; opIdx < totalOps; opIdx++) {
		query query;
		in >> query.opType;
		if (query.opType == 1) {
			in >> query.s;
			strings.push_back({query.s.size(), query.s});
		} else {
			in >> query.K;
		}
		queries.push_back(query);
 	}

 	sort(strings.begin(), strings.end());
 	strings.erase(unique(strings.begin(), strings.end()), strings.end());

 	for (int opIdx = 0; opIdx < totalOps; opIdx++) {
 		if (queries[opIdx].opType == 1) {
 			pair<int, string> entry = {queries[opIdx].s.size(), queries[opIdx].s};
 			queries[opIdx].key = lower_bound(strings.begin(), strings.end(), entry) - strings.begin();
 		}
 	}
}

int main() {
	srand(time(0));

	preProcessQueries();

	pnode root = NULL;
	for (int opIdx = 0; opIdx < totalOps; opIdx++) {
		if (queries[opIdx].opType == 1) {
			root = insert(root, queries[opIdx].key);
		} else {
			pnode kThElement = findKth(root, queries[opIdx].K);
			string s = strings[kThElement -> key].second;
			out << s << "\n";
		}
	}
	return 0;
}