Submission #1116240

# Submission time Handle Problem Language Result Execution time Memory
1116240 2024-11-21T11:27:42 Z hamzabc Hard route (IZhO17_road) C++14
100 / 100
679 ms 124488 KB
#include <bits/stdc++.h>
 
 
using namespace std;
 
 
#define all(x) x.begin(), x.end()
#define mod 1000000007
#define sp << " " <<
#define endl << '\n'
 
#ifdef L
ifstream input("input.txt");
#define cin input
#else
// #define USACO
#ifdef USACO
ifstream input("atlarge.in");
ofstream output("atlarge.out");
#define cin input
#define cout output
#endif
#endif


vector<vector<int>> graph;
vector<long long int> dist;
vector<long long int> distind;
vector<long long int> distmul;
long long int hard = 0;
long long int cnt = 0;
int n;



void dp(int node = 0, int parent = -1){
	for (auto go : graph[node]){
		if (go == parent)
			continue;
		dp(go, node);
		if (dist[node] < dist[go] + 1){
			dist[node] = dist[go] + 1;
			distmul[node] = distmul[go];
		}else if (dist[node] == dist[go] + 1){
			distmul[node] += distmul[go];
		}
	}
}

void reroot(int node = 0, int parent = -1, long long int parentdist = -1, long long int parentmul = 1){
	long long int big1 = parentdist + 1, big2 = 0, big3 = 0;
	long long int mul1 = parentmul, mul2 = 0, mul3 = 0;
	for (int go : graph[node]){
		if (go == parent)
			continue;
		if (dist[go] + 1 > big1){
			big3 = big2;
			mul3 = mul2;
			big2 = big1;
			mul2 = mul1;
			big1 = dist[go] + 1;
			mul1 = distmul[go];
		}else if (dist[go] + 1 > big2){
			big3 = big2;
			mul3 = mul2;
			big2 = dist[go] + 1;
			mul2 = distmul[go];
		}else if (dist[go] + 1 > big3){
			big3 = dist[go] + 1;
			mul3 = distmul[go];
		}
	}
	long long int deg1 = big1 * (big2 + big3);
	if (graph[node].size() > 2 && deg1 > hard){
		hard = deg1;
	}
	for (int go : graph[node]){
		if (go == parent)
			continue;
		if (big1 == dist[go] + 1){
			reroot(go, node, big2, mul2);
		}else{
			reroot(go, node, big1, mul1);
		}
	}
}

void reroot2(int node = 0, int parent = -1, long long int parentdist = -1, long long int parentmul = 0, bool parentused = true){
	if (graph[node].size() == 0)
		return;
	long long int big1 = parentdist + 1, big2 = 0, big3 = 0;
	long long int mul1 = max(parentmul, 1LL), mul2 = 0, mul3 = 0;
	long long int smul1 = parentmul, smul2 = 0;
	long long int num1 = !parentused, num2 = 0, num3 = 0;
	if (parentused){
		big1 = 0;
		mul1 = 0;
	}
	for (int go : graph[node]){
		if (go == parent)
			continue;
		if (dist[go] + 1 == big1){
			mul1 += distmul[go];
			smul1 += distmul[go] * distmul[go];
			num1++;
		}else if (dist[go] + 1 == big2){
			mul2 += distmul[go];
			smul2 += distmul[go] * distmul[go];
			num2++;
		}else if (dist[go] + 1 == big3){
			mul3 += distmul[go];
			num3++;
		}else if (dist[go] + 1 > big1){
			big3 = big2;
			mul3 = mul2;
			num3 = num2;
			big2 = big1;
			mul2 = mul1;
			num2 = num1;
			smul2 = smul1;
			big1 = dist[go] + 1;
			mul1 = distmul[go];
			num1 = 1;
			smul1 = mul1 * mul1;
		}else if (dist[go] + 1 > big2){
			big3 = big2;
			mul3 = mul2;
			num3 = num2;
			big2 = dist[go] + 1;
			mul2 = distmul[go];
			smul2 = mul2 * mul2;
			num2 = 1;
		}else if (dist[go] + 1 > big3){
			big3 = dist[go] + 1;
			mul3 = distmul[go];
			num3 = 1;
		}
	}
	// cerr << node sp "|" sp big1 sp mul1 sp num1 sp "|" sp big2 sp mul2 sp num2 sp "|" sp big3 sp mul3 sp num3 sp "|" sp parentused sp "pd:"sp parentdist + 1 sp parentmul endl;
	bool flag1 = false, flag2 = false;
	if (parentused && (big1 + big2) * (parentdist + 1) == hard){
		cnt += mul2 * mul1;
		if (((parentdist + 1) + big2) * big1 == hard)
			cnt += parentmul * mul2;
		flag1 = true;
		flag2 = true;
	}else if (parentused && (num1 > 1 && (2 * big1 * (parentdist + 1)) == hard)){
		cnt += (mul1 * mul1 - smul1) / 2;
		if (((parentdist + 1) + big2) * big1 == hard)
			cnt += parentmul * mul2;
		flag1 = true;
		flag2 = true;
	}else if (big1 * (big2 + big3) == hard || (num2 > 1 && big1 * big2 * 2 == hard) || (num1 > 1 && big1 * (big1 + big2) == hard) || (num1 > 2 && big1 * big1 * 2 == hard)){
		if (num1 > 2){
			cnt += (mul1 * mul1 - smul1) / 2;
			flag2 = true;
			flag1 = true;
		}else if (num1 > 1){
			cnt += mul2 * mul1;
			flag2 = true;
			flag1 = true;
		}else if (num2 > 1){
			cnt += (mul2 * mul2 - smul2) / 2;
			flag1 = true;
		}else{
			cnt += mul2 * mul3;
			flag1 = true;
		}
	}
	for (int go : graph[node]){
		if (go == parent)
			continue;
		if (parentused){
			if (big1 == dist[go] + 1 && num1 > 1 && big1 >= parentdist + 1)
				reroot2(go, node, big1, mul1 - distmul[go], flag2);
			else if (big1 != dist[go] + 1 && big1 >= parentdist + 1){
				reroot2(go, node, big1, mul1, flag2);
			}else if (big2 >= parentdist + 1){
				reroot2(go, node, big2, mul2, flag1);
			}else{
				reroot2(go, node, parentdist + 1, parentmul, true);
			}
		}else{
			if (big1 == dist[go] + 1 && num1 == 1){
				reroot2(go, node, big2, mul2, flag1);
			}else if (big1 == dist[go] + 1 && num1 > 1)
				reroot2(go, node, big1, mul1 - distmul[go], flag2);
			else
				reroot2(go, node, big1, mul1, flag2);
		}
	}
}


signed main() {
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	cin >> n;
	graph.resize(n);
	dist.resize(n, 0);
	distind.resize(n);
	distmul.resize(n, 1);
	for (int i = 0; i < n - 1; i++){
		int a, b;
		cin >> a >> b;
		a--; b--;
		graph[a].push_back(b);
		graph[b].push_back(a);
	}
	dp();
	reroot();
	reroot2();
	cout << hard sp max(1LL, cnt);
}

Compilation message

road.cpp: In function 'void reroot(int, int, long long int, long long int)':
road.cpp:52:44: warning: variable 'mul3' set but not used [-Wunused-but-set-variable]
   52 |  long long int mul1 = parentmul, mul2 = 0, mul3 = 0;
      |                                            ^~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Output is correct
2 Correct 1 ms 336 KB Output is correct
3 Correct 1 ms 336 KB Output is correct
4 Correct 1 ms 336 KB Output is correct
5 Correct 1 ms 336 KB Output is correct
6 Correct 1 ms 336 KB Output is correct
7 Correct 1 ms 336 KB Output is correct
8 Correct 1 ms 336 KB Output is correct
9 Correct 1 ms 336 KB Output is correct
10 Correct 1 ms 336 KB Output is correct
11 Correct 1 ms 336 KB Output is correct
12 Correct 1 ms 336 KB Output is correct
13 Correct 1 ms 504 KB Output is correct
14 Correct 1 ms 504 KB Output is correct
15 Correct 1 ms 336 KB Output is correct
16 Correct 1 ms 336 KB Output is correct
17 Correct 1 ms 336 KB Output is correct
18 Correct 1 ms 336 KB Output is correct
19 Correct 1 ms 336 KB Output is correct
20 Correct 1 ms 464 KB Output is correct
21 Correct 1 ms 336 KB Output is correct
22 Correct 1 ms 336 KB Output is correct
23 Correct 1 ms 336 KB Output is correct
24 Correct 1 ms 336 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Output is correct
2 Correct 1 ms 336 KB Output is correct
3 Correct 1 ms 336 KB Output is correct
4 Correct 1 ms 336 KB Output is correct
5 Correct 1 ms 336 KB Output is correct
6 Correct 1 ms 336 KB Output is correct
7 Correct 1 ms 336 KB Output is correct
8 Correct 1 ms 336 KB Output is correct
9 Correct 1 ms 336 KB Output is correct
10 Correct 1 ms 336 KB Output is correct
11 Correct 1 ms 336 KB Output is correct
12 Correct 1 ms 336 KB Output is correct
13 Correct 1 ms 504 KB Output is correct
14 Correct 1 ms 504 KB Output is correct
15 Correct 1 ms 336 KB Output is correct
16 Correct 1 ms 336 KB Output is correct
17 Correct 1 ms 336 KB Output is correct
18 Correct 1 ms 336 KB Output is correct
19 Correct 1 ms 336 KB Output is correct
20 Correct 1 ms 464 KB Output is correct
21 Correct 1 ms 336 KB Output is correct
22 Correct 1 ms 336 KB Output is correct
23 Correct 1 ms 336 KB Output is correct
24 Correct 1 ms 336 KB Output is correct
25 Correct 3 ms 1104 KB Output is correct
26 Correct 3 ms 1116 KB Output is correct
27 Correct 3 ms 1104 KB Output is correct
28 Correct 3 ms 1104 KB Output is correct
29 Correct 2 ms 1104 KB Output is correct
30 Correct 3 ms 1104 KB Output is correct
31 Correct 2 ms 1104 KB Output is correct
32 Correct 2 ms 1104 KB Output is correct
33 Correct 2 ms 1036 KB Output is correct
34 Correct 3 ms 1312 KB Output is correct
35 Correct 3 ms 1104 KB Output is correct
36 Correct 2 ms 1080 KB Output is correct
37 Correct 3 ms 1360 KB Output is correct
38 Correct 3 ms 1616 KB Output is correct
39 Correct 3 ms 1104 KB Output is correct
40 Correct 2 ms 848 KB Output is correct
41 Correct 2 ms 848 KB Output is correct
42 Correct 2 ms 848 KB Output is correct
43 Correct 3 ms 848 KB Output is correct
44 Correct 2 ms 884 KB Output is correct
45 Correct 2 ms 848 KB Output is correct
46 Correct 2 ms 592 KB Output is correct
47 Correct 2 ms 848 KB Output is correct
48 Correct 2 ms 1016 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Output is correct
2 Correct 1 ms 336 KB Output is correct
3 Correct 1 ms 336 KB Output is correct
4 Correct 1 ms 336 KB Output is correct
5 Correct 1 ms 336 KB Output is correct
6 Correct 1 ms 336 KB Output is correct
7 Correct 1 ms 336 KB Output is correct
8 Correct 1 ms 336 KB Output is correct
9 Correct 1 ms 336 KB Output is correct
10 Correct 1 ms 336 KB Output is correct
11 Correct 1 ms 336 KB Output is correct
12 Correct 1 ms 336 KB Output is correct
13 Correct 1 ms 504 KB Output is correct
14 Correct 1 ms 504 KB Output is correct
15 Correct 1 ms 336 KB Output is correct
16 Correct 1 ms 336 KB Output is correct
17 Correct 1 ms 336 KB Output is correct
18 Correct 1 ms 336 KB Output is correct
19 Correct 1 ms 336 KB Output is correct
20 Correct 1 ms 464 KB Output is correct
21 Correct 1 ms 336 KB Output is correct
22 Correct 1 ms 336 KB Output is correct
23 Correct 1 ms 336 KB Output is correct
24 Correct 1 ms 336 KB Output is correct
25 Correct 3 ms 1104 KB Output is correct
26 Correct 3 ms 1116 KB Output is correct
27 Correct 3 ms 1104 KB Output is correct
28 Correct 3 ms 1104 KB Output is correct
29 Correct 2 ms 1104 KB Output is correct
30 Correct 3 ms 1104 KB Output is correct
31 Correct 2 ms 1104 KB Output is correct
32 Correct 2 ms 1104 KB Output is correct
33 Correct 2 ms 1036 KB Output is correct
34 Correct 3 ms 1312 KB Output is correct
35 Correct 3 ms 1104 KB Output is correct
36 Correct 2 ms 1080 KB Output is correct
37 Correct 3 ms 1360 KB Output is correct
38 Correct 3 ms 1616 KB Output is correct
39 Correct 3 ms 1104 KB Output is correct
40 Correct 2 ms 848 KB Output is correct
41 Correct 2 ms 848 KB Output is correct
42 Correct 2 ms 848 KB Output is correct
43 Correct 3 ms 848 KB Output is correct
44 Correct 2 ms 884 KB Output is correct
45 Correct 2 ms 848 KB Output is correct
46 Correct 2 ms 592 KB Output is correct
47 Correct 2 ms 848 KB Output is correct
48 Correct 2 ms 1016 KB Output is correct
49 Correct 356 ms 75784 KB Output is correct
50 Correct 342 ms 81228 KB Output is correct
51 Correct 330 ms 85928 KB Output is correct
52 Correct 298 ms 69300 KB Output is correct
53 Correct 258 ms 78412 KB Output is correct
54 Correct 287 ms 83528 KB Output is correct
55 Correct 279 ms 70992 KB Output is correct
56 Correct 273 ms 76616 KB Output is correct
57 Correct 360 ms 89420 KB Output is correct
58 Correct 349 ms 83272 KB Output is correct
59 Correct 372 ms 83016 KB Output is correct
60 Correct 375 ms 80200 KB Output is correct
61 Correct 679 ms 124488 KB Output is correct
62 Correct 633 ms 110204 KB Output is correct
63 Correct 619 ms 69012 KB Output is correct
64 Correct 533 ms 59168 KB Output is correct
65 Correct 523 ms 52732 KB Output is correct
66 Correct 532 ms 49480 KB Output is correct
67 Correct 504 ms 47688 KB Output is correct
68 Correct 523 ms 47176 KB Output is correct
69 Correct 374 ms 46920 KB Output is correct
70 Correct 344 ms 46664 KB Output is correct
71 Correct 314 ms 46408 KB Output is correct
72 Correct 330 ms 46672 KB Output is correct
73 Correct 390 ms 46748 KB Output is correct
74 Correct 473 ms 46920 KB Output is correct
75 Correct 605 ms 46788 KB Output is correct
76 Correct 515 ms 46916 KB Output is correct
77 Correct 359 ms 47624 KB Output is correct
78 Correct 209 ms 48684 KB Output is correct