Submission #107218

#	Time	Username	Problem	Language	Result	Execution time	Memory
107218		eriksuenderhauf	Mergers (JOI19_mergers)	C++11	0 / 100	45 ms	3676 KiB

mergers

//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define mem(a,v) memset((a), (v), sizeof (a))
#define enl printf("\n")
#define case(t) printf("Case #%d: ", (t))
#define ni(n) scanf("%d", &(n))
#define nl(n) scanf("%lld", &(n))
#define nai(a, n) for (int i = 0; i < (n); i++) ni(a[i])
#define nal(a, n) for (int i = 0; i < (n); i++) nl(a[i])
#define pri(n) printf("%d\n", (n))
#define prl(n) printf("%lld\n", (n))
#define pii pair<int, int>
#define pil pair<int, long long>
#define pll pair<long long, long long>
#define vii vector<pii>
#define vil vector<pil>
#define vll vector<pll>
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef cc_hash_table<int,int,hash<int>> ht;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> oset;
const double pi = acos(-1);
const int MOD = 1e9 + 7;
const ll INF = 1e16 + 7;
const int MAXN = 1e6 + 5;
const double eps = 1e-9;
int deg[MAXN], col[MAXN];
pii edg[MAXN];

int main() {
	int n, k;
	scanf("%d %d", &n, &k);
	for (int i = 1; i < n; i++) {
		int u, v;
		scanf("%d %d", &u, &v);
		edg[i] = {--u, --v};
	}
	for (int i = 0; i < n; i++) {
		ni(col[i]); --col[i];
	}
	for (int i = 0; i < n; i++) {
		int u, v; tie(u, v) = edg[i];
		u = col[u], v = col[v];
		if (u == v) continue;
		deg[u]++, deg[v]++;
	}
	int cnt = 0;
	for (int i = 0; i < k; i++)
		if (deg[i] == 1)
			cnt++;
	pri((cnt+1)/2);
    return 0;
}

Compilation message (stderr)

mergers.cpp: In function 'int main()':
mergers.cpp:41:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d", &n, &k);
  ~~~~~^~~~~~~~~~~~~~~~~
mergers.cpp:44:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d", &u, &v);
   ~~~~~^~~~~~~~~~~~~~~~~
mergers.cpp:8:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 #define ni(n) scanf("%d", &(n))
               ~~~~~^~~~~~~~~~~~
mergers.cpp:48:3: note: in expansion of macro 'ni'
   ni(col[i]); --col[i];
   ^~

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