oj.uz

Submission #170354

# Submission time Handle Problem Language Result Execution time Memory
170354 2019-12-24T20:36:24 Z Ruxandra985 Mousetrap (CEOI17_mousetrap) C++14
45 / 100
 1016 ms 81500 KB 
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#define DIMN 1000010
using namespace std;
int fth[DIMN] , w[DIMN] , maxi[DIMN] , t , blocked[DIMN] , niv[DIMN];
int aib[DIMN];
pair <int,int> aint[4*DIMN];
vector <int> v[DIMN];
pair <int,int> s[DIMN];
void dfs (int nod,int tt){
    int i , vecin , maxii = 0 , poz;
    fth[nod] = tt;
    for (i=0;i<v[nod].size();i++){
        vecin = v[nod][i];
        if (vecin != tt){
            niv[vecin] = 1 + niv[nod];
            dfs (vecin , nod);
            /// cat de in jos te poti duce din nod
        }
    }
   // if (nod == 5)
     //   printf ("a");
    /// maxi[nod] = nr de mutari ale soarecelui ca sa se plimbe in subarborele nod
    /// iar apoi sa revina in nod
    poz = -1;
    maxii = -1;
    for (i=0;i<v[nod].size();i++){
        vecin = v[nod][i];
        if (vecin != tt){
            if (maxii < maxi[vecin]){
                maxii = maxi[vecin];
                poz = vecin;
            }
        }
    }
    maxi[nod] = -1;
    int x = v[nod].size();
    for (i=0;i<v[nod].size();i++){
        vecin = v[nod][i];
        if (vecin != tt && vecin != poz){
            maxi[nod] = max (maxi[nod] , maxi[vecin] + 1 + 1 + x - 3);
            /// 1 ca sa cureti drumul vecin , nod dupa ce se blocheaza
            /// 1 ca sa blochezi cel mai nasol pasaj
        }
    }
    if (poz != -1){
        if (maxi[nod] == -1)
            maxi[nod] = maxi[poz] + 1 + x - 2;
        maxi[nod] = min(maxi[nod] , maxi[poz] + 1 + x - 2);
    }
    else maxi[nod] = 0;
    /// pot sa aleg sa nu blochez cel mai nasol pasaj
    if (v[nod].size() == 2){
        maxi[nod] = 1;
    }
}
int cmp (pair <int,int> a , pair <int,int> b){
    if (a.first != b.first)
        return a.first > b.first;
    return a.second < b.second;

}
int main()
{
    FILE *fin = stdin;
    FILE *fout = stdout;
    int n , m , i , x , y , nod , elem , mustblock , poz , sp ,sol , can , tt , el , p;
    int vecin , until;
    fscanf (fin,"%d%d%d",&n,&t,&m);
    for (i=1;i<n;i++){
        fscanf (fin,"%d%d",&x,&y);
        v[x].push_back(y);
        v[y].push_back(x);
    }
    //printf ("%d %d\n",v[t].size() , v[m].size());
    v[m].push_back(0);
    dfs (m , 0);
    /// practic soarecele isi alege un singur subarbore in care se duce cat vrea el
    /// apio cand se blocheaza
    nod = t;
    elem = 0;
    w[++elem] = t;
    while (fth[nod]){
        w[++elem] = fth[nod];
        nod = fth[nod];
    }
    mustblock = 0;
    for (i=1;i<=elem;i++){
        //printf ("%d %d\n",w[i],v[w[i]].size() - 2);
        if (w[i] == t)
            continue;
        mustblock += v[w[i]].size() - 2; /// nici tatal
    }
    sol = 2000000000;
    nod = m;
    can = 0;
    tt = 0;
    poz = elem;
    el = 0;
    nod = m;
    tt = 0;
    int tos = 0;
    /// poti sa blochezi can pasaje in drumul
    can = 0;
    until = 0;
    while (nod != t){
        sp = 0;
        can++;
        tos = 0;
        if (v[nod].size() == 2){ /// efectiv nu ai ce sa faci


        }
        else {
            el = 0;
            for (i=0;i<v[nod].size();i++){
                vecin = v[nod][i];
                if (vecin != tt && vecin != w[elem-1]){
                    s[++el] = make_pair(maxi[vecin] , vecin);

                    tos++;
                    /// 1 ca sa cureti drumul vecin , nod dupa ce se blocheaza
                    /// 1 ca sa blochezi cel mai nasol pasaj
                }
            }
            sort (s + 1 , s + el + 1 , cmp);
            for (i=1;i<=el && can;i++){
                /// pe asta il blochezi la timp
                if (i == el)
                    sol = min( sol ,  maxi[s[i].second] + 1 + mustblock - 1 + until);
                can--;
                until++;
                mustblock--;
            }
            if (!can && i<=el){
                sol = min ( sol ,  maxi[s[i].second] + 1 + mustblock - 1 + until);
                fprintf (fout,"%d\n",sol);
                return 0;
            }
        }

        tt = nod;
        nod = w[elem-1];
        elem--;
    }
    sol = min (sol , until);
    fprintf (fout,"%d",until);
    return 0;
}

Compilation message

mousetrap.cpp: In function 'void dfs(int, int)':
mousetrap.cpp:15:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i=0;i<v[nod].size();i++){
              ~^~~~~~~~~~~~~~
mousetrap.cpp:29:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i=0;i<v[nod].size();i++){
              ~^~~~~~~~~~~~~~
mousetrap.cpp:40:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i=0;i<v[nod].size();i++){
              ~^~~~~~~~~~~~~~
mousetrap.cpp: In function 'int main()':
mousetrap.cpp:118:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (i=0;i<v[nod].size();i++){
                      ~^~~~~~~~~~~~~~
mousetrap.cpp:69:54: warning: variable 'poz' set but not used [-Wunused-but-set-variable]
     int n , m , i , x , y , nod , elem , mustblock , poz , sp ,sol , can , tt , el , p;
                                                      ^~~
mousetrap.cpp:69:60: warning: variable 'sp' set but not used [-Wunused-but-set-variable]
     int n , m , i , x , y , nod , elem , mustblock , poz , sp ,sol , can , tt , el , p;
                                                            ^~
mousetrap.cpp:69:86: warning: unused variable 'p' [-Wunused-variable]
     int n , m , i , x , y , nod , elem , mustblock , poz , sp ,sol , can , tt , el , p;
                                                                                      ^
mousetrap.cpp:71:12: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     fscanf (fin,"%d%d%d",&n,&t,&m);
     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
mousetrap.cpp:73:16: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         fscanf (fin,"%d%d",&x,&y);
         ~~~~~~~^~~~~~~~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 23804 KB Output is correct
2 Correct 23 ms 23928 KB Output is correct
3 Correct 23 ms 23800 KB Output is correct
4 Correct 22 ms 23800 KB Output is correct
5 Correct 23 ms 23800 KB Output is correct
6 Correct 23 ms 23800 KB Output is correct
7 Correct 23 ms 23900 KB Output is correct
8 Correct 23 ms 23800 KB Output is correct
9 Correct 24 ms 23928 KB Output is correct
10 Correct 23 ms 23928 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 436 ms 77196 KB Output is correct
2 Correct 398 ms 74488 KB Output is correct
3 Correct 1016 ms 79464 KB Output is correct
4 Correct 432 ms 52408 KB Output is correct
5 Correct 957 ms 81500 KB Output is correct
6 Correct 966 ms 81280 KB Output is correct

Subtask #3
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 23804 KB Output is correct
2 Correct 23 ms 23928 KB Output is correct
3 Correct 23 ms 23800 KB Output is correct
4 Correct 22 ms 23800 KB Output is correct
5 Correct 23 ms 23800 KB Output is correct
6 Correct 23 ms 23800 KB Output is correct
7 Correct 23 ms 23900 KB Output is correct
8 Correct 23 ms 23800 KB Output is correct
9 Correct 24 ms 23928 KB Output is correct
10 Correct 23 ms 23928 KB Output is correct
11 Correct 23 ms 23800 KB Output is correct
12 Correct 23 ms 23932 KB Output is correct
13 Correct 24 ms 23928 KB Output is correct
14 Correct 23 ms 23928 KB Output is correct
15 Correct 24 ms 24056 KB Output is correct
16 Correct 23 ms 24056 KB Output is correct
17 Incorrect 24 ms 23900 KB Output isn't correct
18 Halted 0 ms 0 KB -

Subtask #4
0 / 35.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 23804 KB Output is correct
2 Correct 23 ms 23928 KB Output is correct
3 Correct 23 ms 23800 KB Output is correct
4 Correct 22 ms 23800 KB Output is correct
5 Correct 23 ms 23800 KB Output is correct
6 Correct 23 ms 23800 KB Output is correct
7 Correct 23 ms 23900 KB Output is correct
8 Correct 23 ms 23800 KB Output is correct
9 Correct 24 ms 23928 KB Output is correct
10 Correct 23 ms 23928 KB Output is correct
11 Correct 436 ms 77196 KB Output is correct
12 Correct 398 ms 74488 KB Output is correct
13 Correct 1016 ms 79464 KB Output is correct
14 Correct 432 ms 52408 KB Output is correct
15 Correct 957 ms 81500 KB Output is correct
16 Correct 966 ms 81280 KB Output is correct
17 Correct 23 ms 23800 KB Output is correct
18 Correct 23 ms 23932 KB Output is correct
19 Correct 24 ms 23928 KB Output is correct
20 Correct 23 ms 23928 KB Output is correct
21 Correct 24 ms 24056 KB Output is correct
22 Correct 23 ms 24056 KB Output is correct
23 Incorrect 24 ms 23900 KB Output isn't correct
24 Halted 0 ms 0 KB -