oj.uz

Submission #68071

# Submission time Handle Problem Language Result Execution time Memory
68071 2018-08-15T21:09:32 Z MKopchev Sorting (IOI15_sorting) C++14
100 / 100
 247 ms 14184 KB 
#include<bits/stdc++.h>
#include "sorting.h"
using namespace std;
const int nmax=2e5+42;
int arr[nmax],where[nmax],inv[nmax];
bool been[nmax];
vector< pair<int,int> > change;
int findSwapPairs(int N,int S[],int M,int X[],int Y[],int P[],int Q[])
{
    memset(been,0,sizeof(been));
    change={};
    int ok=N,not_ok=-1;
    while(ok-not_ok>1)
    {
        int av=(ok+not_ok)/2;
        //test av
        for(int j=0;j<N;j++)
            arr[j]=S[j];

        for(int j=0;j<av;j++)
            swap(arr[X[j]],arr[Y[j]]);

        memset(been,0,sizeof(been));
        int now=0;
        for(int i=0;i<N;i++)
            if(been[i]==0)
            {
                int j=i,d=0;
                while(been[j]==0)
                {
                    been[j]=1;
                    d++;
                    j=arr[j];
                }
                now=now+d-1;
            }
        //cout<<av<<" -> "<<now<<endl;
        if(now<=av)ok=av;
        else not_ok=av;
    }
    for(int j=0;j<N;j++)
        arr[j]=S[j];
    for(int j=0;j<ok;j++)
        swap(arr[X[j]],arr[Y[j]]);

    memset(been,0,sizeof(been));
    for(int i=0;i<N;i++)
        if(been[i]==0)
        {
            int j=i,d=0;
            while(been[j]==0)
            {
                been[j]=1;
                d++;
                j=arr[j];
                if(i!=j)change.push_back({min(i,j),max(i,j)});
            }

        }
    while(change.size()<ok)
    {
        change.push_back({0,0});
    }
    for(auto k:change)
    {
    swap(arr[k.first],arr[k.second]);
    }

    for(int i=0;i<N;i++)
        if(arr[i]!=i)return -1;//???
    int SZ=change.size();
    //reverse(change.begin(),change.end());
    /*
    cout<<"change: "<<endl;
    for(auto k:change)cout<<k.first<<" "<<k.second<<endl;
    */
    /*
    for(int i=0;i<SZ;i++)
    {
        pair<int,int> now=change[i];
        for(int j=ok-1;j>i;j--)
        {
            if(X[j]==now.first&&Y[j]==now.second)continue;
            if(X[j]==now.second&&Y[j]==now.first)continue;
            int a=-1,b=-1,q=-1;
            if(X[j]==now.first)a=X[j],b=Y[j],q=now.second;
            else if(Y[j]==now.first)a=Y[j],b=X[j],q=now.second;
            else if(X[j]==now.second)a=X[j],b=Y[j],q=now.first;
            else if(Y[j]==now.second)a=Y[j],b=X[j],q=now.first;
            if(a!=-1)now={b,q};
            //cout<<"after "<<j<<" step, "<<now.first<<" "<<now.second<<endl;
        }
        P[i]=now.first;
        Q[i]=now.second;
        //cout<<i<<" -> "<<now.first<<" "<<now.second<<endl;
    }
    */
    for(int j=0;j<N;j++)
        where[j]=j,inv[j]=j;
    for(int i=ok-1;i>=0;i--)
    {
        P[i]=where[change[i].first];
        Q[i]=where[change[i].second];
        swap(where[inv[X[i]]],where[inv[Y[i]]]);
        swap(inv[X[i]],inv[Y[i]]);
    }
    //test
    for(int j=0;j<N;j++)
        arr[j]=S[j];
    for(int i=0;i<ok;i++)
    {
        swap(arr[X[i]],arr[Y[i]]);
        swap(arr[P[i]],arr[Q[i]]);
        //for(int j=0;j<N;j++)cout<<arr[j]<<" ";cout<<endl;
    }

    for(int i=0;i<N;i++)
        if(arr[i]!=i)
        {
            cout<<"---"<<endl;
            cout<<ok<<endl;
            for(int j=0;j<ok;j++)cout<<P[j]<<" "<<Q[j]<<endl;
            for(int j=0;j<N;j++)cout<<arr[j]<<" ";cout<<endl;
            system("pause");
        }

    return ok;
}
/*
int n=5;
int S[5]={4,3,2,1,0};
int m=6;
int X[6]={0,1,2,3,0,1};
int Y[6]={1,2,3,4,1,2};
int P[6];
int Q[6];
*/
/*
int n=3;
int S[3]={0,2,1};
int m=3;
int X[3]={0,1,2};
int Y[3]={1,2,0};
int P[3];
int Q[3];
*/
/*
const int n=5;
int S[n];
const int m=6;
int X[m]={1,4,2,1,0};
int Y[m]={1,0,3,4,4};
int P[m];
int Q[m];
int main()
{
    srand(time(0));
    while(1)
    {
        for(int j=0;j<n;j++)S[j]=j;
        random_shuffle(S,S+n);
        for(int j=0;j<m;j++)
        {
            X[j]=rand()%n;
            Y[j]=rand()%n;
        }
        cout<<n<<" : ";for(int j=0;j<n;j++)cout<<S[j]<<" ";cout<<endl;
        cout<<m<<endl;
        for(int j=0;j<m;j++)cout<<X[j]<<" "<<Y[j]<<endl;
        cout<<findSwapPairs(n,S,m,X,Y,P,Q)<<endl;
        cout<<endl;
    }
}
*/

Compilation message

sorting.cpp: In function 'int findSwapPairs(int, int*, int, int*, int*, int*, int*)':
sorting.cpp:60:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     while(change.size()<ok)
           ~~~~~~~~~~~~~^~~
sorting.cpp:71:23: warning: conversion to 'int' from 'std::vector<std::pair<int, int> >::size_type {aka long unsigned int}' may alter its value [-Wconversion]
     int SZ=change.size();
            ~~~~~~~~~~~^~
sorting.cpp:123:13: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
             for(int j=0;j<N;j++)cout<<arr[j]<<" ";cout<<endl;
             ^~~
sorting.cpp:123:51: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
             for(int j=0;j<N;j++)cout<<arr[j]<<" ";cout<<endl;
                                                   ^~~~
sorting.cpp:71:9: warning: unused variable 'SZ' [-Wunused-variable]
     int SZ=change.size();
         ^~
sorting.cpp:8:37: warning: unused parameter 'M' [-Wunused-parameter]
 int findSwapPairs(int N,int S[],int M,int X[],int Y[],int P[],int Q[])
                                     ^
sorting.cpp:124:19: warning: ignoring return value of 'int system(const char*)', declared with attribute warn_unused_result [-Wunused-result]
             system("pause");
             ~~~~~~^~~~~~~~~

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 512 KB Output is correct
2 Correct 3 ms 512 KB Output is correct
3 Correct 3 ms 512 KB Output is correct
4 Correct 3 ms 512 KB Output is correct
5 Correct 3 ms 512 KB Output is correct
6 Correct 3 ms 512 KB Output is correct
7 Correct 3 ms 512 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 512 KB Output is correct
2 Correct 3 ms 512 KB Output is correct
3 Correct 3 ms 512 KB Output is correct
4 Correct 3 ms 512 KB Output is correct
5 Correct 3 ms 512 KB Output is correct
6 Correct 3 ms 512 KB Output is correct
7 Correct 3 ms 512 KB Output is correct
8 Correct 2 ms 612 KB Output is correct
9 Correct 2 ms 640 KB Output is correct
10 Correct 2 ms 768 KB Output is correct
11 Correct 3 ms 512 KB Output is correct
12 Correct 2 ms 512 KB Output is correct

Subtask #3
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 512 KB Output is correct
2 Correct 3 ms 512 KB Output is correct
3 Correct 3 ms 512 KB Output is correct
4 Correct 2 ms 512 KB Output is correct
5 Correct 2 ms 512 KB Output is correct
6 Correct 2 ms 512 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 512 KB Output is correct
2 Correct 3 ms 512 KB Output is correct
3 Correct 3 ms 512 KB Output is correct
4 Correct 3 ms 512 KB Output is correct
5 Correct 3 ms 512 KB Output is correct
6 Correct 3 ms 512 KB Output is correct
7 Correct 3 ms 512 KB Output is correct
8 Correct 2 ms 612 KB Output is correct
9 Correct 2 ms 640 KB Output is correct
10 Correct 2 ms 768 KB Output is correct
11 Correct 3 ms 512 KB Output is correct
12 Correct 2 ms 512 KB Output is correct
13 Correct 2 ms 512 KB Output is correct
14 Correct 3 ms 512 KB Output is correct
15 Correct 3 ms 512 KB Output is correct
16 Correct 2 ms 512 KB Output is correct
17 Correct 2 ms 512 KB Output is correct
18 Correct 2 ms 512 KB Output is correct
19 Correct 2 ms 512 KB Output is correct
20 Correct 3 ms 512 KB Output is correct
21 Correct 4 ms 640 KB Output is correct
22 Correct 5 ms 640 KB Output is correct
23 Correct 4 ms 768 KB Output is correct
24 Correct 3 ms 640 KB Output is correct
25 Correct 3 ms 640 KB Output is correct
26 Correct 3 ms 640 KB Output is correct
27 Correct 3 ms 640 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 640 KB Output is correct
2 Correct 3 ms 640 KB Output is correct
3 Correct 5 ms 640 KB Output is correct
4 Correct 4 ms 640 KB Output is correct
5 Correct 3 ms 640 KB Output is correct
6 Correct 3 ms 640 KB Output is correct
7 Correct 3 ms 640 KB Output is correct
8 Correct 3 ms 640 KB Output is correct
9 Correct 5 ms 640 KB Output is correct
10 Correct 4 ms 640 KB Output is correct
11 Correct 4 ms 640 KB Output is correct
12 Correct 4 ms 640 KB Output is correct
13 Correct 3 ms 640 KB Output is correct
14 Correct 3 ms 640 KB Output is correct

Subtask #6
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 640 KB Output is correct
2 Correct 3 ms 640 KB Output is correct
3 Correct 5 ms 640 KB Output is correct
4 Correct 4 ms 640 KB Output is correct
5 Correct 3 ms 640 KB Output is correct
6 Correct 3 ms 640 KB Output is correct
7 Correct 3 ms 640 KB Output is correct
8 Correct 3 ms 640 KB Output is correct
9 Correct 5 ms 640 KB Output is correct
10 Correct 4 ms 640 KB Output is correct
11 Correct 4 ms 640 KB Output is correct
12 Correct 4 ms 640 KB Output is correct
13 Correct 3 ms 640 KB Output is correct
14 Correct 3 ms 640 KB Output is correct
15 Correct 152 ms 11892 KB Output is correct
16 Correct 182 ms 12136 KB Output is correct
17 Correct 219 ms 13032 KB Output is correct
18 Correct 62 ms 7800 KB Output is correct
19 Correct 157 ms 10860 KB Output is correct
20 Correct 160 ms 11372 KB Output is correct
21 Correct 168 ms 11628 KB Output is correct
22 Correct 171 ms 12884 KB Output is correct
23 Correct 176 ms 13292 KB Output is correct
24 Correct 214 ms 13288 KB Output is correct
25 Correct 209 ms 13416 KB Output is correct
26 Correct 153 ms 11244 KB Output is correct
27 Correct 138 ms 10568 KB Output is correct
28 Correct 179 ms 12904 KB Output is correct
29 Correct 193 ms 12776 KB Output is correct
30 Correct 100 ms 9840 KB Output is correct
31 Correct 206 ms 13160 KB Output is correct
32 Correct 176 ms 12648 KB Output is correct
33 Correct 216 ms 13388 KB Output is correct
34 Correct 192 ms 13164 KB Output is correct
35 Correct 139 ms 10860 KB Output is correct
36 Correct 49 ms 8312 KB Output is correct
37 Correct 222 ms 14184 KB Output is correct
38 Correct 214 ms 13456 KB Output is correct
39 Correct 247 ms 13680 KB Output is correct