Submission #481016

#	Time	Username	Problem	Language	Result	Execution time	Memory
481016		PiejanVDC	Connecting Supertrees (IOI20_supertrees)	C++17	21 / 100	233 ms	24076 KiB

supertrees

#include "supertrees.h"
#include <bits/stdc++.h>
using namespace std;

void build(std::vector<std::vector<int>> _b);

vector<int>parent;

int UF(int u) {
    if(parent[u] == u)
        return u;
    return parent[u] = UF(parent[u]);
}

int construct(vector<vector<int>> p) {
    const int n = (int)p.size();
    parent.resize(n);
    vector<vector<int>>ans(n,vector<int>(n,0));
    for(int i = 0 ; i < n ; i++)
        parent[i] = i;
    for(int i = 0 ; i < n ; i++) {
        for(int j = i+1 ; j < n ; j++) {
            if(p[i][j] == 3) {
                return 0; // invalid
            }
            assert(p[i][j] == p[j][i]);
            if(p[i][j] == 1) {
                int u = UF(i), v = UF(j);
                if(u != v) {
                    ans[i][j] = ans[j][i] = 1;
                    parent[u] = v;
                }
            }
        }
    }
    for(int i = 0 ; i < n ; i++) {
        for(int j = i+1 ; j < n ; j++) {
            if(p[i][j] == 0 && UF(i) == UF(j)) {
                return 0;
            }
        }
    }
    build(ans);
    return 1;
}

/*

static int n;
static std::vector<std::vector<int>> p;
static std::vector<std::vector<int>> b;
static bool called = false;

static void check(bool cond, std::string message) {
    if (!cond) {
        printf("%s\n", message.c_str());
        fclose(stdout);
        exit(0);
    }
}

void build(std::vector<std::vector<int>> _b) {
    check(!called, "build is called more than once");
    called = true;
    check((int)_b.size() == n, "Invalid number of rows in b");
    for (int i = 0; i < n; i++) {
        check((int)_b[i].size() == n, "Invalid number of columns in b");
    }
    b = _b;
}

int main() {
    assert(scanf("%d", &n) == 1);

    p.resize(n);
    for (int i = 0; i < n; i++) {
        p[i].resize(n);
    }

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            assert(scanf("%d", &p[i][j]) == 1);
        }
    }

    int possible = construct(p);

    check(possible == 0 || possible == 1, "Invalid return value of construct");
    if (possible == 1) {
        check(called, "construct returned 1 without calling build");
    } else {
        check(!called, "construct called build but returned 0");
    }

    printf("%d\n", possible);
    if (possible == 1) {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                if (j) {
                    printf(" ");
                }
                printf("%d", b[i][j]);
            }
            printf("\n");
        }
    }
}*/

• Subtask 1: 11 / 11
• Subtask 2: 10 / 10
• Subtask 3: 0 / 19
• Subtask 4: 0 / 35
• Subtask 5: 0 / 21
• Subtask 6: 0 / 4