Submission #609709

#	Time	Username	Problem	Language	Result	Execution time	Memory
609709		strange420	Roller Coaster Railroad (IOI16_railroad)	C++14	0 / 100	444 ms	28420 KiB

railroad

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

#define MAXN 500000

int fenwick[MAXN], n;

void fenwickPointUpdate(int i, int val) {
    i++;

    while (i <= n) {
        fenwick[i] += val;
        i += i & (-i);
    }
}

void fenwickUpdate(int l, int r) {
    fenwickPointUpdate(l, 1);
    fenwickPointUpdate(r, -1);
}

int getSum(int x) {
    int sum = 0;
    while (x > 0) {
        sum += fenwick[x];
        x -= x & (-x);
    }
    return sum;
}

int fenwickQuery(int x) {
    x--; return getSum(x) - getSum(x-1);
}

long long plan_roller_coaster(std::vector<int> s, std::vector<int> t) {
    n = (int) s.size();

    vector<int> asd;
    for (int x: s) asd.push_back(x);
    for (int x: t) asd.push_back(x);

    sort(asd.begin(), asd.end());
    map<int,int> indexing;
    for (int i=0; i<asd.size(); i++)
        indexing[asd[i]] = i;

    for (int i=0; i<n; i++) {
        s[i] = indexing[s[i]];
        t[i] = indexing[t[i]];
    }

    for (int i=0; i<n; i++) fenwickUpdate(s[i], t[i] + 1);
    
    for (int i=0; i<2*n; i++)
        if (fenwickQuery(i) > 0) return 1;
    return 0;
}

Compilation message (stderr)

railroad.cpp: In function 'long long int plan_roller_coaster(std::vector<int>, std::vector<int>)':
railroad.cpp:45:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |     for (int i=0; i<asd.size(); i++)
      |                   ~^~~~~~~~~~~

• Subtask 1: 0 / 11
• Subtask 2: 0 / 23
• Subtask 3: 0 / 30
• Subtask 4: 0 / 36