Submission #32031

# Submission time Handle Problem Language Result Execution time Memory
32031 2017-09-23T03:08:08 Z minimario Beads and wires (APIO14_beads) C++14
100 / 100
249 ms 26220 KB
#include <bits/stdc++.h>
using namespace std;

#define f first
#define s second
const int MAX = 200005;
typedef pair<int, int> pii;

vector<pii> g[MAX];
int dp[MAX][2][2];

int max(int a, int b, int c) { return max(max(a, b), c); }
int max(int a, int b, int c, int d) { return max(max(a, b), max(c, d)); }

void dfs(int u, int p=-1, int len=-1) {
	for (pii i : g[u]) {
		if (i.f == p) { continue; }
		dfs(i.f, u, i.s);
	}
	int sum = 0, sum2 = 0;
	vector<pii> val0, val1;
	for (pii i : g[u]) {
		if (i.f == p) { continue; }
		sum += max(dp[i.f][0][0], dp[i.f][1][0]);
		val0.push_back({max(dp[i.f][0][0], dp[i.f][1][0]) - dp[i.f][0][0] - i.s, i.f});
		val1.push_back({max(dp[i.f][0][0], dp[i.f][1][0]) - dp[i.f][0][1] - i.s, i.f});

	}
	sort(val0.begin(), val0.end());
	sort(val1.begin(), val1.end());
	for (int i=0; i<min(2, (int)val0.size()); i++) {
		for (int j=0; j<min(2, (int)val1.size()); j++) {
			if (val0[i].s != val1[j].s) {
				dp[u][0][1] = max(dp[u][0][1], sum - val0[i].f - val1[j].f);
			}
		}
	}
	if (val0.size() >= 2) {
		dp[u][0][1] = max(dp[u][0][1], sum - val0[0].f - val0[1].f);
	}
	if (p != -1) {
		for (pii i : g[u]) {
			if (i.f == p) { continue; }
			dp[u][1][0] = max(dp[u][1][0], len + sum - max(dp[i.f][0][0], dp[i.f][1][0]) + dp[i.f][0][0] + i.s);
			dp[u][1][1] = max(dp[u][1][1], len + sum - max(dp[i.f][0][0], dp[i.f][1][0]) + dp[i.f][0][1] + i.s);
		}
	}
	dp[u][0][0] = sum;
	for (pii i : g[u]) {
		if (i.f == p) { continue; }
		dp[u][0][1] = max(dp[u][0][1], sum - max(dp[i.f][0][0], dp[i.f][1][0]) + max(dp[i.f][0][1], dp[i.f][1][1]));
	}
	// cout << u << " " << dp[u][0][0] << " " << dp[u][0][1] << " " << dp[u][1][0] << " " << dp[u][1][1] << endl; 
}
int main() {
	// freopen("a.in", "r", stdin);
	// freopen("a.out", "w", stdout);
	int n; scanf("%d", &n);
	for (int i=0; i<n-1; i++) {
		int u, v, w; scanf("%d %d %d", &u, &v, &w);
		g[u].push_back({v, w});
		g[v].push_back({u, w});
	}
	dfs(1);
	printf("%d\n", max(dp[1][0][0], dp[1][0][1], dp[1][1][0], dp[1][1][1]));
}

Compilation message

beads.cpp: In function 'void dfs(int, int, int)':
beads.cpp:20:15: warning: unused variable 'sum2' [-Wunused-variable]
  int sum = 0, sum2 = 0;
               ^~~~
beads.cpp: In function 'int main()':
beads.cpp:58:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  int n; scanf("%d", &n);
         ~~~~~^~~~~~~~~~
beads.cpp:60:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   int u, v, w; scanf("%d %d %d", &u, &v, &w);
                ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 6 ms 5004 KB Output is correct
2 Correct 6 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 12 ms 4992 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 4992 KB Output is correct
7 Correct 6 ms 4992 KB Output is correct
8 Correct 6 ms 4992 KB Output is correct
9 Correct 7 ms 4992 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 5 ms 4992 KB Output is correct
12 Correct 6 ms 4992 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 6 ms 5004 KB Output is correct
2 Correct 6 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 12 ms 4992 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 4992 KB Output is correct
7 Correct 6 ms 4992 KB Output is correct
8 Correct 6 ms 4992 KB Output is correct
9 Correct 7 ms 4992 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 5 ms 4992 KB Output is correct
12 Correct 6 ms 4992 KB Output is correct
13 Correct 5 ms 4992 KB Output is correct
14 Correct 6 ms 4992 KB Output is correct
15 Correct 6 ms 4992 KB Output is correct
16 Correct 6 ms 4992 KB Output is correct
17 Correct 5 ms 4992 KB Output is correct
18 Correct 6 ms 4992 KB Output is correct
19 Correct 6 ms 4992 KB Output is correct
20 Correct 6 ms 4992 KB Output is correct
21 Correct 6 ms 5120 KB Output is correct
22 Correct 6 ms 5120 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 6 ms 5004 KB Output is correct
2 Correct 6 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 12 ms 4992 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 4992 KB Output is correct
7 Correct 6 ms 4992 KB Output is correct
8 Correct 6 ms 4992 KB Output is correct
9 Correct 7 ms 4992 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 5 ms 4992 KB Output is correct
12 Correct 6 ms 4992 KB Output is correct
13 Correct 5 ms 4992 KB Output is correct
14 Correct 6 ms 4992 KB Output is correct
15 Correct 6 ms 4992 KB Output is correct
16 Correct 6 ms 4992 KB Output is correct
17 Correct 5 ms 4992 KB Output is correct
18 Correct 6 ms 4992 KB Output is correct
19 Correct 6 ms 4992 KB Output is correct
20 Correct 6 ms 4992 KB Output is correct
21 Correct 6 ms 5120 KB Output is correct
22 Correct 6 ms 5120 KB Output is correct
23 Correct 9 ms 5376 KB Output is correct
24 Correct 8 ms 5248 KB Output is correct
25 Correct 9 ms 5300 KB Output is correct
26 Correct 13 ms 5476 KB Output is correct
27 Correct 12 ms 5504 KB Output is correct
28 Correct 13 ms 6016 KB Output is correct
29 Correct 12 ms 5632 KB Output is correct
30 Correct 13 ms 5632 KB Output is correct
31 Correct 13 ms 6400 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 6 ms 5004 KB Output is correct
2 Correct 6 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 12 ms 4992 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 4992 KB Output is correct
7 Correct 6 ms 4992 KB Output is correct
8 Correct 6 ms 4992 KB Output is correct
9 Correct 7 ms 4992 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 5 ms 4992 KB Output is correct
12 Correct 6 ms 4992 KB Output is correct
13 Correct 5 ms 4992 KB Output is correct
14 Correct 6 ms 4992 KB Output is correct
15 Correct 6 ms 4992 KB Output is correct
16 Correct 6 ms 4992 KB Output is correct
17 Correct 5 ms 4992 KB Output is correct
18 Correct 6 ms 4992 KB Output is correct
19 Correct 6 ms 4992 KB Output is correct
20 Correct 6 ms 4992 KB Output is correct
21 Correct 6 ms 5120 KB Output is correct
22 Correct 6 ms 5120 KB Output is correct
23 Correct 9 ms 5376 KB Output is correct
24 Correct 8 ms 5248 KB Output is correct
25 Correct 9 ms 5300 KB Output is correct
26 Correct 13 ms 5476 KB Output is correct
27 Correct 12 ms 5504 KB Output is correct
28 Correct 13 ms 6016 KB Output is correct
29 Correct 12 ms 5632 KB Output is correct
30 Correct 13 ms 5632 KB Output is correct
31 Correct 13 ms 6400 KB Output is correct
32 Correct 42 ms 7748 KB Output is correct
33 Correct 45 ms 7808 KB Output is correct
34 Correct 44 ms 7760 KB Output is correct
35 Correct 232 ms 15584 KB Output is correct
36 Correct 236 ms 15620 KB Output is correct
37 Correct 238 ms 15608 KB Output is correct
38 Correct 214 ms 20836 KB Output is correct
39 Correct 192 ms 18688 KB Output is correct
40 Correct 211 ms 17256 KB Output is correct
41 Correct 249 ms 26220 KB Output is correct