Submission #129653

#	Time	Username	Problem	Language	Result	Execution time	Memory
129653		pzdba	Izlet (COI19_izlet)	C++14	100 / 100	1086 ms	74760 KiB

izlet

#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;
int c[3002][3002], cnt[3002];
vector<pii> edge;
vector<int> g[3002];
struct dsu{
    int p[3002];
    int root(int a){
        return p[a] == a?a:(p[a]=root(p[a]));
    }
    void merge(int a, int b){
        a = root(a), b = root(b);
        if(a != b) p[a] = b;
    }
}d[2];

bool vis[3002];
int check[3002];
int dfs2(int u, int p, int cur){
    for(int i=0;i<g[u].size();i++){
        int v = g[u][i];
        if(!vis[v]) continue;
        if(v == p) continue;

        if(c[cur][u] == c[cur][v] && check[cnt[v]] == 0) return cnt[v];

        check[cnt[v]]++;
        int val = dfs2(v, u, cur);
        if(val != -1) return val;
        check[cnt[v]]--;
    }
    return -1;
}

int co = 1;
void dfs1(int u, int p){
    vis[u] = 1;

    memset(check, 0, sizeof(check));
    int val = dfs2(u, 0, u);
    if(val == -1) cnt[u] = co++;
    else cnt[u] = val;

    for(int i=0;i<g[u].size();i++){
        int v = g[u][i];
        if(v == p) continue;
        dfs1(v, u);
    }
}

int main(){
    int t, n;
    scanf("%d", &t);
    scanf("%d", &n);
    for(int i=1;i<=n;i++) d[0].p[i] = d[1].p[i] = i;
    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++){
            scanf("%d", &c[i][j]);
            if(c[i][j] == 1 && d[0].root(i) != d[0].root(j)){
                edge.push_back(pii(i, j));
                d[0].merge(i, j);
                d[1].merge(i, j);
            }
        }
    }

    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++){
            if(c[i][j] == 2 && d[0].root(i) != d[0].root(j)){
                edge.push_back(pii(i, j));
                d[0].merge(i, j);
                g[d[1].root(i)].push_back(d[1].root(j));
                g[d[1].root(j)].push_back(d[1].root(i));
            }
        }
    }

    dfs1(d[1].root(1), 0);
    for(int i=1;i<=n;i++) printf("%d ", cnt[d[1].root(i)]);
    printf("\n");
    for(int i=0;i<n-1;i++) printf("%d %d\n", edge[i].first, edge[i].second);
}

Compilation message (stderr)

izlet.cpp: In function 'int dfs2(int, int, int)':
izlet.cpp:21:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<g[u].size();i++){
                 ~^~~~~~~~~~~~
izlet.cpp: In function 'void dfs1(int, int)':
izlet.cpp:45:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<g[u].size();i++){
                 ~^~~~~~~~~~~~
izlet.cpp: In function 'int main()':
izlet.cpp:54:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &t);
     ~~~~~^~~~~~~~~~
izlet.cpp:55:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~
izlet.cpp:59:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d", &c[i][j]);
             ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 18 / 18
• Subtask 2: 25 / 25
• Subtask 3: 57 / 57