Submission #613780

# Submission time Handle Problem Language Result Execution time Memory
613780 2022-07-30T10:49:50 Z drdilyor Ancient Books (IOI17_books) C++17
0 / 100
1 ms 340 KB
#include <bits/stdc++.h>
#include "books.h"
#ifdef ONPC
    #include "t_debug.cpp"
#else
    #define debug(...) 42
#endif
#define sz(a) ((int)(a).size())
using namespace std;
using ll = long long;
const int INF = 1e9;
const ll INFL = 1e18;
const int RANDOM = chrono::high_resolution_clock::now().time_since_epoch().count();
mt19937 rng(RANDOM);
template<typename T, typename U> istream& operator>>(istream& is, pair<T, U>& p) { return is >> p.first >> p.second; }
const int N = 2e5, LOGN = 17, MOD = 1e9+7;

struct DSU {
    int n;
    vector<int> parent;
    vector<int> size;

    DSU(int n) : n(n), parent(n), size(n, 1) {
        iota(parent.begin(), parent.end(), 0);
    }

    int get(int i) {
        return parent[i] == i ? i : parent[i] = get(parent[i]);
    }

    void merge(int v, int u) {
        v = get(v);
        u = get(u);
        if (u == v) return;
        if (size[v] < size[u]) swap(v, u);
        parent[v] = u;
        size[v] += size[u];
    }
};

long long minimum_walk(std::vector<int> p, int s) {
    int n = sz(p);
    vector<vector<int>> cycles;
    vector<pair<int,int>> range;
    vector<int> done(n);
    int distance = 0;
    int mnstart = -1;
    for (int i = 0; i < n; i++) {
        distance += abs(p[i] - i);
        if (done[i]) continue;
        if (p[i] == i) continue;
        done[i] = true;
        if (mnstart==-1) mnstart =i;
        cycles.push_back({i});
        for (int cur = p[i]; !done[cur]; cur = p[cur]) {
            cycles.back().push_back(cur);
            done[cur] = true;
        }
    }

    int k = sz(cycles);
    if (!k) return 0;

    for (int i = 0; i < k; i++) {
        int l = INF, r = 0;
        for (int i : cycles[i]) {
            l = min(l, i);
            r = max(r, i);
        }
        range.emplace_back(l, r);
    }

    DSU groups(n);
    for (int i = 0; i < k; i++) {
        for (int j = range[i].first;j < range[i].second; j++) {
            groups.merge(j, j+1);
        }
    }
    int disjoint = 0;
    for (int i = mnstart; i < n-1; i++) {
        if (groups.get(i) != groups.get(i+1)) {
            disjoint++;
        }
    }

    int waste = disjoint * 2;
    debug(cycles, range);
    debug(waste, disjoint);

    return distance + (mnstart == -1 ? 0 : mnstart * 2) + waste;
}

Compilation message

books.cpp: In function 'long long int minimum_walk(std::vector<int>, int)':
books.cpp:6:24: warning: statement has no effect [-Wunused-value]
    6 |     #define debug(...) 42
      |                        ^~
books.cpp:87:5: note: in expansion of macro 'debug'
   87 |     debug(cycles, range);
      |     ^~~~~
books.cpp:6:24: warning: statement has no effect [-Wunused-value]
    6 |     #define debug(...) 42
      |                        ^~
books.cpp:88:5: note: in expansion of macro 'debug'
   88 |     debug(waste, disjoint);
      |     ^~~~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Incorrect 1 ms 212 KB 3rd lines differ - on the 1st token, expected: '4', found: '6'
6 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Incorrect 1 ms 212 KB 3rd lines differ - on the 1st token, expected: '4', found: '6'
6 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Incorrect 1 ms 212 KB 3rd lines differ - on the 1st token, expected: '4', found: '6'
6 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 340 KB 3rd lines differ - on the 1st token, expected: '3304', found: '2744'
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Incorrect 1 ms 212 KB 3rd lines differ - on the 1st token, expected: '4', found: '6'
6 Halted 0 ms 0 KB -