Submission #332900

#	Time	Username	Problem	Language	Result	Execution time	Memory
332900		ly20	Mergers (JOI19_mergers)	C++17	10 / 100	45 ms	37356 KiB

mergers

#include <bits/stdc++.h>
using namespace std;
const int MAXN = 3123;
int marc[MAXN], tp[MAXN], sub[MAXN][MAXN];
int n, k;
vector <int> grafo[MAXN];
int vl[MAXN];
int resp = 0;
void dfs1(int v, int p) {
    for(int i = 0; i < grafo[v].size(); i++) {
        int viz = grafo[v][i];
        if(viz == p) continue;
        dfs1(viz, v);
        for(int j = 1; j <= k; j++) {
            sub[v][j] += sub[viz][j];
        }
        vl[v] += vl[viz];
    }
    bool ok = true;
    for(int i = 1; i <= k; i++) {
        if(sub[v][i] != marc[i] && sub[v][i] != 0) ok = false;
    }
    if(ok) vl[v]++;
    if(p == v) return;
    if(ok && vl[v] == 1) resp++;
}
int main() {
    scanf("%d %d", &n, &k);
    for(int i = 0; i < n - 1; i++) {
        int a, b;
        scanf("%d %d", &a, &b);
        grafo[a].push_back(b); grafo[b].push_back(a);
    }
    for(int i = 1 ; i<= n; i++) {
        int a;
        scanf("%d", &a);
        marc[a]++; tp[i] = a; sub[i][a]++;
    }
    if(n == 2) {
        if(tp[1] == tp[2]) printf("0\n");
        else printf("1\n");
        return 0;
    }
    int prox = 1;
    for(int i = 1; i <= n; i++) if(grafo[i].size() > 1) prox = i;
    dfs1(prox, prox);
    printf("%d\n", (resp + 1) / 2);
    return 0;
}

Compilation message (stderr)

mergers.cpp: In function 'void dfs1(int, int)':
mergers.cpp:10:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |     for(int i = 0; i < grafo[v].size(); i++) {
      |                    ~~^~~~~~~~~~~~~~~~~
mergers.cpp: In function 'int main()':
mergers.cpp:28:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   28 |     scanf("%d %d", &n, &k);
      |     ~~~~~^~~~~~~~~~~~~~~~~
mergers.cpp:31:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   31 |         scanf("%d %d", &a, &b);
      |         ~~~~~^~~~~~~~~~~~~~~~~
mergers.cpp:36:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   36 |         scanf("%d", &a);
      |         ~~~~~^~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 0 / 24
• Subtask 3: 0 / 14
• Subtask 4: 0 / 22
• Subtask 5: 0 / 30