Submission #899748

#	Time	Username	Problem	Language	Result	Execution time	Memory
899748		Pekiban	KOVANICE (COI15_kovanice)	C++17	100 / 100	160 ms	54708 KiB

kovanice

#include <bits/stdc++.h>
    
using namespace std;
    
array<int, 3> f(string s) {
    int i = 0, x = 0;
    array<int, 3> a;
    while (s[i] != '<' && s[i] != '>' && s[i] != '=') {
        x*=10;
        x += (s[i] - '0');
        i++;
    }
    a[0] = x, a[1] = (s[i] == '<' ? 0 : (s[i] == '>' ? 1 : 2));
    x = 0, i++;
    while (i < s.size()) {
        x*=10;
        x += (s[i] - '0');
        i++;
    }
    a[2] = x;
    return a;
}
const int mxN = 3e5+2;
int p[mxN], sz[mxN], mx[mxN], ans[mxN];
bool visited[mxN];
vector<int> g[mxN], mxv[mxN], dir[mxN], ord;
int findset(int s) {
    if (s == p[s])  return s;
    return p[s] = findset(p[s]);
}
void unite(int u, int v) {
    u = findset(u), v = findset(v);
    if (u == v) return;
    if (sz[u] < sz[v])  swap(u, v);
    p[v] = u;
    sz[u] += sz[v];
}
void dfs(int s) {
    visited[s] = 1;
    for (auto u : g[s]) {
        if (visited[u]) continue;
        dfs(u);
    }
    ord.push_back(s);
}
void dfspush(int s, int x) {
    visited[s] = 1;
    ans[s] = x;     
    for (auto u : mxv[s]) {
        if (visited[u]) continue;
        dfspush(u, x-1);
    }
}
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    iota(p, p+mxN, 0); fill(sz, sz+mxN, 1);
    int n, m, v;
    cin >> n >> m >> v;
    for (int i = 0; i < v; ++i) {
        string s;
        cin >> s;
        auto [x, r, y] = f(s);
        if (r == 2) {
            unite(x, y);
        }
        else if (r == 1) {
            dir[x].push_back(y);
        }
        else {
            dir[y].push_back(x);
        }
    }
    for (int i = 1; i <= m; ++i) {
        for (auto u : dir[i]) {
            g[findset(i)].push_back(findset(u));
        }
    }
    for (int i = 1; i <= m; ++i) {
        if (!visited[findset(i)]) {
            dfs(findset(i));
        }
    }
    for (auto i : ord) {
        for (auto u : g[i]) {
            mx[i] = max(mx[i], mx[u]+1);
        }
        for (auto u : g[i]) {
            if (mx[u]+1 == mx[i]) {
                mxv[i].push_back(u);
            }
        }
    }
    fill(visited, visited+mxN, 0);
    for (auto i : ord) {
        if (mx[i] == n-1) {
            dfspush(i, n);
        }
    }
    for (int i = 1; i <= m; ++i) {
        if (ans[findset(i)]) {
            cout << "K" << ans[findset(i)] << '\n';
        }
        else {
            cout << "?" << '\n';
        }
    }
}

Compilation message (stderr)

kovanice.cpp: In function 'std::array<int, 3> f(std::string)':
kovanice.cpp:15:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |     while (i < s.size()) {
      |            ~~^~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 40 / 40
• Subtask 3: 10 / 10
• Subtask 4: 40 / 40