Submission #306348

# Submission time Handle Problem Language Result Execution time Memory
306348 2020-09-25T09:19:46 Z syy Deda (COCI17_deda) C++17
140 / 140
585 ms 26496 KB
#include <bits/stdc++.h>
using namespace std;
#define int long long
typedef pair <int, int> pi; //Station, child

struct node { // Creates a struct for the node of a seg tree
    int s, e, m;
    pi v; // start, end, middle, rangemin value
    node *l, *r; // pointer to left, right subnodes
    node(int _s, int _e) { //Constructor to create nodes l and r
        s = _s; e = _e; m = (s+e)/2; // initialize variables
        v.second = INT_MAX;
        v.first = INT_MAX;
        if (s!=e) { // is not a leaf node
            l = new node(s, m); // create child nodes
            r = new node(m+1, e);
        }
    }
    void up(int x, int nv) { //update position x to nv (new value)
        if (s==e) { //if node is a leaf, just modify v.
			v = pi(nv, x);
			return;
		}
        if (x>m) r->up(x, nv); //update right subtree if update is in right subtree
        if (x<=m) l->up(x, nv); //update left subtree if update is in left subtree
        v = min(l->v, r->v); //Modify the value of v after updating children
    }
    pi rmq(int x, int y) { //range min query from position x, y
        if (s==x && e==y) return v; //return range min if query range corresponds
        if (x>m) return r->rmq(x, y); //query right tree if range only lies there
        if (y<=m) return l->rmq(x, y); //query left tree if range only lies there
        return min(l->rmq(x, m), r->rmq(m+1, y)); //minimum of both queries as range spans both trees
    }
} *root; // declares root as a pointer node. Root is the name of the segment tree.

int n, q, a, b;
char x;

int32_t main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cin >> n >> q;
	root = new node(1, n);
	for (int i = 0; i < q; i++) {
		cin >> x >> a >> b;
		if (x == 'M') root -> up(b, a);
		else {
			int counter = 0;
			int c;
			pi cur, previ;
			c = n;
			while (true) {
				counter++;
				cur = root -> rmq(b, c);
				if (cur.first > a && counter == 1) {
					cout << -1 << "\n";
					break;
				} else if (cur.second == b && cur.first <= a) {
					cout << cur.second << "\n";
					break;
				} else if (cur.first > a) {
					cout << previ.second << "\n";
					break;
				}
				previ = cur;
				c = cur.second - 1;
			}
		}
	}
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 4 ms 512 KB Output is correct
4 Correct 325 ms 26496 KB Output is correct
5 Correct 418 ms 13688 KB Output is correct
6 Correct 490 ms 20088 KB Output is correct
7 Correct 585 ms 26360 KB Output is correct