Submission #429833

#	Time	Username	Problem	Language	Result	Execution time	Memory
429833		schse	Handcrafted Gift (IOI20_gift)	C++17	25 / 100	721 ms	19004 KiB

gift

#include "gift.h"
#include <bits/stdc++.h>
using namespace std;
#ifndef EVAL
#include "grader.cpp"
#endif

struct segtree
{
    vector<int> tree = vector<int>(1 << 20, -1);

    void lazzy(int index)
    {
        if (tree[index] != -1)
            tree[index * 2] = tree[index * 2 + 1] = tree[index];
        tree[index] = -1;
    }

    void iota(int index, int b, int e)
    {
        if (e - b == 1)
        {
            tree[index] = b;
            return;
        }
        iota(index * 2, b, (b + e) / 2);
        iota(index * 2 + 1, (b + e) / 2, e);
    }

    void updset(int index, int b, int e, int l, int r, int v)
    {
        if (l <= b && e <= r)
        {
            tree[index] = v;
            return;
        }
        if (e <= l || r <= b)
            return;
        lazzy(index);
        updset(index * 2, b, (b + e) / 2, l, r, v);
        updset(index * 2 + 1, (b + e) / 2, e, l, r, v);
    }

    int query(int index, int b, int e, int p)
    {
        if (p < b || p >= e)
            return 0;
        if (e - b == 1 && b == p)
            return tree[index];
        lazzy(index);
        return query(index * 2, b, (b + e) / 2, p) + query(index * 2 + 1, (b + e) / 2, e, p);
    }
} tree;

int construct(int n, int r, std::vector<int> a, std::vector<int> b, std::vector<int> x)
{

    tree.iota(1, 0, n);

    vector<int> prefix(n);
    iota(prefix.begin(), prefix.end(), 0);
    for (int i = 0; i < a.size(); i++) //update single color
    {
        if (x[i] == 1)
        {
            int va = tree.query(1, 0, n, a[i]);
            int vb = tree.query(1, 0, n, b[i]);
            tree.updset(1, 0, n, a[i], b[i] + 1, va);
        }
    }
    for (int i = 0; i < a.size(); i++) //check wetherpossible
    {
        if (x[i] == 2)
        {
            int va = tree.query(1, 0, n, a[i]);
            int vb = tree.query(1, 0, n, b[i]);
            if (vb == va)
                return 0;
        }
    }
    std::string s(n, 'R');
    bool bo = true;
    int last = -1;
    for (int i = 0; i < n; i++)
    {
        int v = tree.query(1, 0, n, i);
        if (v != last)
        {
            last = v;
            bo = !bo;
        }
        s[i] = bo ? 'R' : 'B';
    }
    craft(s);
    return 1;
}

Compilation message (stderr)

gift.cpp: In function 'int construct(int, int, std::vector<int>, std::vector<int>, std::vector<int>)':
gift.cpp:62:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |     for (int i = 0; i < a.size(); i++) //update single color
      |                     ~~^~~~~~~~~~
gift.cpp:67:17: warning: unused variable 'vb' [-Wunused-variable]
   67 |             int vb = tree.query(1, 0, n, b[i]);
      |                 ^~
gift.cpp:71:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   71 |     for (int i = 0; i < a.size(); i++) //check wetherpossible
      |                     ~~^~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 0 / 20
• Subtask 4: 0 / 25
• Subtask 5: 0 / 30