Submission #775287

#	Time	Username	Problem	Language	Result	Execution time	Memory
775287		boris_mihov	Gondola (IOI14_gondola)	C++17	100 / 100	42 ms	6592 KiB

gondola

#include "gondola.h"
#include <algorithm>
#include <iostream>
#include <cassert>
#include <numeric>
#include <vector>
#include <set>

typedef long long llong;
const int MAXNUM = 250000 + 10;
const int MAXN = 100000 + 10;
const int MOD  = 1e9 + 9;
const int INF  = 1e9;

std::set <int> s;

llong power(llong num, llong base)
{
    if (base == 0)
    {
        return 1;
    }

    if (base & 1)
    {
        return (num * power(num, base - 1)) % MOD;
    }

    llong res = power(num, base / 2);
    return (res * res) % MOD;
}

int n;
int getPosDiff(int last, int curr)
{
    if (last > curr)
    {
        return n - last + curr;
    }

    return curr - last;
}

int valid(int N, int inputSeq[])
{
    n = N;
    int minPos = 0;
    for (int i = 1 ; i < n ; ++i)
    {
        if (s.count(inputSeq[i]))
        {
            return 0;
        }

        s.insert(inputSeq[i]);
        if (inputSeq[i] < inputSeq[minPos])
        {
            minPos = i;
        }
    }

    if (inputSeq[minPos] > n)
    {
        return 1;
    }

    for (int i = minPos - 1 ; i >= std::max(0, minPos - inputSeq[minPos] + 1) ; --i)
    {
        if (inputSeq[i] <= n)
        {
            return 0;
        }
    }

    if (minPos + 1 < inputSeq[minPos])
    {
        for (int i = n - 1 ; i >= n + minPos + 1 - inputSeq[minPos] ; --i)
        {
            if (inputSeq[i] <= n)
            {
                return 0;
            }
        }
    }

    int lastPos = minPos;
    int last = inputSeq[minPos];
    for (int i = minPos + 1 ; i < n ; ++i)
    {
        if (inputSeq[i] <= n)
        {
            if (last > inputSeq[i])
            {
                return 0;
            }
            
            if (getPosDiff(lastPos, i) != inputSeq[i] - last)
            {
                return 0;
            }

            last = inputSeq[i];
            lastPos = i;
        }
    }

    for (int i = 1 ; i < minPos ; ++i)
    {
        if (inputSeq[i] <= n)
        {
            if (last > inputSeq[i])
            {
                return 0;
            }
            
            if (getPosDiff(lastPos, i) != inputSeq[i] - last)
            {
                return 0;
            }

            last = inputSeq[i];
            lastPos = i;
        }
    }

    return 1;
}

//----------------------

int a[MAXN];
int res[MAXNUM];
int sorted[MAXN];
int replacement(int N, int gondolaSeq[], int replacementSeq[])
{
    n = N;
    int minPos = 0;
    for (int i = 1 ; i < n ; ++i)
    {
        if (gondolaSeq[i] < gondolaSeq[minPos])
        {
            minPos = i;
        }
    }

    int cnt = gondolaSeq[minPos];
    if (cnt > n) cnt = 1;

    for (int i = minPos ; i < n ; ++i)
    {
        a[i] = cnt++;
        if (cnt == n + 1)
        {
            cnt = 1;
        }
    }

    for (int i = 0 ; i < minPos ; ++i)
    {
        a[i] = cnt++;
        if (cnt == n + 1)
        {
            cnt = 1;
        }
    }

    std::iota(sorted, sorted + n, 0);
    std::sort(sorted, sorted + n, [&](int x, int y)
    {
        return gondolaSeq[x] < gondolaSeq[y];
    });

    int len = 0, reached = n;
    for (int i = 0 ; i < n ; ++i)
    {
        if (gondolaSeq[sorted[i]] <= reached)
        {
            assert(gondolaSeq[sorted[i]] <= n);
            continue;
        }

        replacementSeq[len++] = a[sorted[i]];
        reached++;

        while (gondolaSeq[sorted[i]] > reached)
        {
            replacementSeq[len++] = reached;
            reached++;
        }
    }

    return len;
}

//----------------------

int countReplacement(int N, int inputSeq[])
{
    if (!valid(N, inputSeq))
    {
        return 0;
    }
    
    n = N;
    std::vector <int> vals;
    for (int i = 0 ; i < n ; ++i)
    {
        if (inputSeq[i] > n)
        {
            vals.push_back(inputSeq[i]);
        }
    }

    int last = n;
    llong ans = 1;
    std::sort(vals.begin(), vals.end());
    for (int i = 0 ; i < vals.size() ; ++i)
    {
        ans *= power(vals.size() - i, vals[i] - last - 1);
        last = vals[i];
        ans %= MOD;
    }

    if (vals.size() == n)
    {
        ans *= n;
        ans %= MOD;
    }
    return ans;
}

Compilation message (stderr)

gondola.cpp: In function 'int countReplacement(int, int*)':
gondola.cpp:217:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  217 |     for (int i = 0 ; i < vals.size() ; ++i)
      |                      ~~^~~~~~~~~~~~~
gondola.cpp:224:21: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  224 |     if (vals.size() == n)
      |         ~~~~~~~~~~~~^~~~

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 10 / 10
• Subtask 4: 5 / 5
• Subtask 5: 10 / 10
• Subtask 6: 20 / 20
• Subtask 7: 5 / 5
• Subtask 8: 15 / 15
• Subtask 9: 15 / 15
• Subtask 10: 10 / 10