Submission #1884022


Source Code Expand

// Shik and Travel
// * frank_c1
// * 2017 / 12 / 18
 
#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;

const int maxn = (1 << 17) + 5;
int wi[maxn], ai[maxn], bi[maxn];
int st[maxn], su[maxn];
pii ci[maxn * 17], ta[maxn], tb[maxn];
int n, idx;

bool chk(int x) {
	idx = 0;
	for (int i = n; i >= 1; --i) {
		st[i] = idx + 1;
		if (!ai[i]) ci[++idx] = make_pair(0, 0);
		else {
			int u = ai[i], v = bi[i];
			if (su[u] > su[v]) swap(u, v);
			int mx = x - wi[u] - wi[v];
			int ca = 0, cb = 0, ww = (int)(1e9), ps = 1;
			for (int j = st[u]; j < st[u] + su[u]; ++j) ta[++ca] = make_pair(ci[j].first, ci[j].second);
			for (int j = st[v]; j < st[v] + su[v]; ++j) tb[++cb] = make_pair(ci[j].second, ci[j].first);
			sort(ta + 1, ta + ca + 1); sort(tb + 1, tb + cb + 1);
			for (int j = ca; j >= 1; --j) {
				while (ps <= cb && ta[j].first + tb[ps].first <= mx) ww = min(ww, tb[ps++].second);	
				if (ps > 1) ci[++idx] = make_pair(ww + wi[v], ta[j].second + wi[u]);
			}
			ca = cb = 0; ww = (int)(1e9); ps = 1;
			for (int j = st[u]; j < st[u] + su[u]; ++j) ta[++ca] = make_pair(ci[j].second, ci[j].first);
			for (int j = st[v]; j < st[v] + su[v]; ++j) tb[++cb] = make_pair(ci[j].first, ci[j].second);
			sort(ta + 1, ta + ca + 1); sort(tb + 1, tb + cb + 1);
			for (int j = ca; j >= 1; --j) {
				while (ps <= cb && ta[j].first + tb[ps].first <= mx) ww = min(ww, tb[ps++].second);
				if (ps > 1) ci[++idx] = make_pair(ta[j].second + wi[u], ww + wi[v]);
			}
		}
		su[i] = idx - st[i] + 1;
	}
	return su[1] > 0;
}

int main() {
	scanf("%d", &n);
	for (int i = 2; i <= n; ++i) {
		int f; scanf("%d%d", &f, &wi[i]);
		if (!ai[f]) ai[f] = i; else bi[f] = i;
	}
	int l = 0, r = 17 * (1 << 17);
	while (l < r) {
		int mid = (l + r) >> 1;
		if (chk(mid)) r = mid; else l = mid + 1;
	}
	return printf("%d\n", l), 0;
}

Submission Info

Submission Time
Task E - Shik and Travel
User frank_c1
Language C++14 (GCC 5.4.1)
Score 0
Code Size 1895 Byte
Status WA
Exec Time 740 ms
Memory 14592 KB

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:47:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
                 ^
./Main.cpp:49:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   int f; scanf("%d%d", &f, &wi[i]);
                                   ^

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 0 / 1400
Status
AC × 4
AC × 49
WA × 5
Set Name Test Cases
Sample example0.txt, example1.txt, example2.txt, example3.txt
All 000.txt, 001.txt, 002.txt, 003.txt, 004.txt, 005.txt, 006.txt, 007.txt, 008.txt, 009.txt, 010.txt, 011.txt, 012.txt, 013.txt, 014.txt, 015.txt, 016.txt, 017.txt, 018.txt, 019.txt, 020.txt, 021.txt, 022.txt, 023.txt, 024.txt, 025.txt, 026.txt, 027.txt, 028.txt, 029.txt, 030.txt, 031.txt, 032.txt, 033.txt, 034.txt, 035.txt, 036.txt, 037.txt, 038.txt, 039.txt, 040.txt, 041.txt, 042.txt, 043.txt, 044.txt, 045.txt, 046.txt, 047.txt, 048.txt, 049.txt, example0.txt, example1.txt, example2.txt, example3.txt
Case Name Status Exec Time Memory
000.txt AC 4 ms 4352 KB
001.txt AC 4 ms 4352 KB
002.txt AC 4 ms 4352 KB
003.txt AC 4 ms 4352 KB
004.txt AC 4 ms 4352 KB
005.txt AC 4 ms 4352 KB
006.txt AC 4 ms 4352 KB
007.txt AC 4 ms 4352 KB
008.txt AC 4 ms 4352 KB
009.txt AC 4 ms 4352 KB
010.txt AC 160 ms 7936 KB
011.txt AC 159 ms 7936 KB
012.txt AC 157 ms 7936 KB
013.txt AC 158 ms 7936 KB
014.txt AC 158 ms 7936 KB
015.txt AC 158 ms 7936 KB
016.txt AC 158 ms 7936 KB
017.txt AC 165 ms 7936 KB
018.txt AC 158 ms 7936 KB
019.txt AC 163 ms 7936 KB
020.txt AC 158 ms 7936 KB
021.txt AC 160 ms 7936 KB
022.txt AC 159 ms 7936 KB
023.txt AC 159 ms 7936 KB
024.txt AC 160 ms 7936 KB
025.txt AC 159 ms 7936 KB
026.txt AC 158 ms 7936 KB
027.txt AC 158 ms 7936 KB
028.txt AC 158 ms 7936 KB
029.txt AC 159 ms 7936 KB
030.txt AC 671 ms 14080 KB
031.txt AC 706 ms 14592 KB
032.txt AC 740 ms 14592 KB
033.txt AC 659 ms 14080 KB
034.txt AC 683 ms 14080 KB
035.txt WA 373 ms 9984 KB
036.txt WA 328 ms 9472 KB
037.txt WA 334 ms 9472 KB
038.txt WA 324 ms 9472 KB
039.txt WA 240 ms 9984 KB
040.txt AC 654 ms 14080 KB
041.txt AC 717 ms 14592 KB
042.txt AC 717 ms 14592 KB
043.txt AC 717 ms 14592 KB
044.txt AC 81 ms 5888 KB
045.txt AC 96 ms 5888 KB
046.txt AC 96 ms 5888 KB
047.txt AC 96 ms 5888 KB
048.txt AC 96 ms 5888 KB
049.txt AC 2 ms 4352 KB
example0.txt AC 2 ms 4352 KB
example1.txt AC 2 ms 4352 KB
example2.txt AC 2 ms 4352 KB
example3.txt AC 2 ms 4352 KB