Submission #209062

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
209062	2020-03-13T04:32:18 Z	Fischer	Mag (COCI16_mag)	C++14	120 / 120	705 ms	229056 KB

#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e6 + 10;
vector<int> g[maxn], len[maxn];
int a[maxn];
int memo[maxn];
int n;

void add(int x, int t) {
	if (len[x][0] <= t) swap(len[x][0], t);
	len[x][1] = max(len[x][1], t);
}

int get(int x, int t=0) {
	return (a[x] == 1) * (len[x][t] + 1);
}

int dfs(int x, int p = 0) {
	len[x] = {0, 0};
	for (int v : g[x]) {
		if (v == p) continue;
		add(x, dfs(v, x));
	}
	return get(x);
}

int dfs_root(int x, int p = 0) {
	if (p) {
		int l = (a[p] == 1) *  get(p, len[p][0] == get(x));
		add(x, l);
	}
	memo[x] = len[x][0] + len[x][1];
	for (int v : g[x]) {
		if (v == p) continue;
		dfs_root(v, x);
	}
}

int main() {
	scanf("%d", &n);
	for (int i = 1; i <= n-1; ++i) {
		int a, b;
		scanf("%d %d", &a, &b);
		g[a].emplace_back(b);
		g[b].emplace_back(a);
	}
	for (int i = 1; i <= n; ++i) {
		scanf("%d", a+i);
	}
	dfs(1);
	dfs_root(1);
	int x = -1, y = -1;
	for (int i = 1; i <= n; ++i) {
		if (x == -1 or x *1ll* (memo[i] + 1) > a[i] *1ll* y) {
			x = a[i];
			y = memo[i] + 1;
		}
	}
	int g = __gcd(x, y);
	printf("%d/%d\n", x/g, y/g);
	return 0;
}

Compilation message

mag.cpp: In function 'int dfs_root(int, int)':
mag.cpp:37:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
mag.cpp: In function 'int main()':
mag.cpp:40:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
  ~~~~~^~~~~~~~~~
mag.cpp:43:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d", &a, &b);
   ~~~~~^~~~~~~~~~~~~~~~~
mag.cpp:48:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", a+i);
   ~~~~~^~~~~~~~~~~

Subtask #1
12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	33 ms	47352 KB	Output is correct
2	Correct	33 ms	47352 KB	Output is correct

Subtask #2
12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	32 ms	47352 KB	Output is correct
2	Correct	34 ms	47352 KB	Output is correct

Subtask #3
12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	543 ms	155148 KB	Output is correct

Subtask #4
12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	31 ms	47224 KB	Output is correct
2	Correct	689 ms	225536 KB	Output is correct

Subtask #5
12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	672 ms	224676 KB	Output is correct

Subtask #6
12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	594 ms	132604 KB	Output is correct
2	Correct	437 ms	110056 KB	Output is correct

Subtask #7
12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	586 ms	135556 KB	Output is correct
2	Correct	136 ms	55928 KB	Output is correct
3	Correct	705 ms	229056 KB	Output is correct

Subtask #8
12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	140 ms	55800 KB	Output is correct
2	Correct	591 ms	133452 KB	Output is correct
3	Correct	566 ms	90744 KB	Output is correct

Subtask #9
12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	537 ms	128368 KB	Output is correct
2	Correct	575 ms	133368 KB	Output is correct

Subtask #10
12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	597 ms	133688 KB	Output is correct
2	Correct	539 ms	90744 KB	Output is correct