Submission #1817929


Source Code Expand

#include <iostream>
#include <cstdio>
#include <set>
#include <vector>
#include <algorithm>
#define rep(i,a,b) for(int i = a; i <= b; i++)
#define Rep(i,a) for(int i = 0; i < a; i++)
using namespace std;
const int N = 2e5 + 10;

struct edge{ int to, pre; } e[N << 1]; int l = 0, u[N];
void ins(int a, int b) { e[++l] = (edge){b, u[a]}, u[a] = l; }
#define v e[i].to
#define reg(i,a) for(int i = u[a]; i; i = e[i].pre)

int n, X, Y, a[N], b[N], dep[N], fa[N];

void dfs(int x, int f) {
	reg(i,x) if (v != f) dep[v] = dep[x] + 1, fa[v] = x, dfs(v, x);
}

bool jump(int a, int b) {
	if (dep[a] < dep[b]) swap(a, b);
	if (fa[a] == b || fa[fa[a]] == b || fa[a] == fa[b]) return false;
	else return true;
}

vector<int> adj[N];
#define pb(a) push_back(a)

bool inf = false, win[N];
int ans = 0;
void chk(int x, int f, int d) {
	if (d >= dep[x]) return; else ans = max(ans, dep[x]);
	inf |= win[x]; int l = adj[x].size();
	Rep(j,l) if (adj[x][j] != f) chk(adj[x][j], x, d + 1);
}

int main() {
	scanf("%d%d%d",&n,&X,&Y);
	rep(i,1,n - 1) scanf("%d%d",a + i,b + i);
	rep(i,1,n - 1) {
		int a, b; scanf("%d%d",&a,&b);
		ins(a, b), ins(b, a);
	}
	dfs(Y, 0);
	rep(i,1,n - 1) 
		if (!jump(a[i], b[i])) 
			adj[a[i]].pb(b[i]), adj[b[i]].pb(a[i]);
		else win[a[i]] = win[b[i]] = true;
	chk(X, 0, 0);
	if (inf) printf("-1\n");
	else printf("%d\n",ans * 2);
	return 0;
}

Submission Info

Submission Time
Task E - Sugigma: The Showdown
User WuHongxun
Language C++14 (GCC 5.4.1)
Score 1400
Code Size 1407 Byte
Status AC
Exec Time 126 ms
Memory 26240 KB

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:40:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d",&n,&X,&Y);
                          ^
./Main.cpp:41:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  rep(i,1,n - 1) scanf("%d%d",a + i,b + i);
                                          ^
./Main.cpp:43:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   int a, b; scanf("%d%d",&a,&b);
                                ^

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 1400 / 1400
Status
AC × 5
AC × 103
Set Name Test Cases
Sample example0, example1, example2, example3, example4
All doublestar0, doublestar1, doublestar2, doublestar3, doublestar4, doublestar5, doublestar6, doublestar7, example0, example1, example2, example3, example4, giri0, giri1, giri2, giri3, giri4, giri5, giri6, giri7, giri8, giri9, maxrand0, maxrand1, maxrand2, maxrand3, maxrand4, maxrand5, maxrand6, maxrand7, maxrand8, maxrand9, narashi0, narashi1, narashi2, narashi3, narashi4, narashi5, narashi6, narashi7, narashi8, narashi9, ok0, ok1, ok2, ok3, ok4, ok5, ok6, ok7, ok8, ok9, ouh0, ouh1, ouh2, ouh3, ouh4, ouh5, ouh6, ouh7, ouh8, ouh9, same0, same1, same2, same3, same4, same5, same6, same7, same8, same9, sameline0, sameline1, sameline2, sameline3, sameline4, sameline5, sameline6, sameline7, sameline8, sameline9, star0, star1, star2, star3, star4, star5, star6, star7, star8, star9, supersmall0, supersmall1, supersmall2, supersmall3, supersmall4, supersmall5, supersmall6, supersmall7, supersmall8, supersmall9
Case Name Status Exec Time Memory
doublestar0 AC 92 ms 15096 KB
doublestar1 AC 77 ms 13312 KB
doublestar2 AC 78 ms 13440 KB
doublestar3 AC 74 ms 13312 KB
doublestar4 AC 80 ms 13696 KB
doublestar5 AC 84 ms 14716 KB
doublestar6 AC 75 ms 13312 KB
doublestar7 AC 78 ms 14204 KB
example0 AC 4 ms 10240 KB
example1 AC 4 ms 10240 KB
example2 AC 4 ms 10240 KB
example3 AC 3 ms 10240 KB
example4 AC 3 ms 10240 KB
giri0 AC 103 ms 18816 KB
giri1 AC 103 ms 18176 KB
giri2 AC 105 ms 18304 KB
giri3 AC 103 ms 18176 KB
giri4 AC 108 ms 18176 KB
giri5 AC 108 ms 18560 KB
giri6 AC 107 ms 18432 KB
giri7 AC 105 ms 18304 KB
giri8 AC 107 ms 18304 KB
giri9 AC 105 ms 18432 KB
maxrand0 AC 80 ms 12160 KB
maxrand1 AC 78 ms 12160 KB
maxrand2 AC 80 ms 12160 KB
maxrand3 AC 79 ms 12032 KB
maxrand4 AC 76 ms 12032 KB
maxrand5 AC 76 ms 12032 KB
maxrand6 AC 76 ms 12032 KB
maxrand7 AC 79 ms 12160 KB
maxrand8 AC 76 ms 12032 KB
maxrand9 AC 78 ms 12032 KB
narashi0 AC 110 ms 18048 KB
narashi1 AC 106 ms 18048 KB
narashi2 AC 102 ms 18176 KB
narashi3 AC 106 ms 18304 KB
narashi4 AC 109 ms 18304 KB
narashi5 AC 104 ms 18432 KB
narashi6 AC 107 ms 18176 KB
narashi7 AC 106 ms 18560 KB
narashi8 AC 107 ms 18432 KB
narashi9 AC 103 ms 18176 KB
ok0 AC 107 ms 23936 KB
ok1 AC 107 ms 24704 KB
ok2 AC 108 ms 22784 KB
ok3 AC 109 ms 24960 KB
ok4 AC 113 ms 22784 KB
ok5 AC 112 ms 22656 KB
ok6 AC 110 ms 24192 KB
ok7 AC 109 ms 22400 KB
ok8 AC 108 ms 23808 KB
ok9 AC 106 ms 23040 KB
ouh0 AC 92 ms 19328 KB
ouh1 AC 98 ms 20096 KB
ouh2 AC 95 ms 20608 KB
ouh3 AC 102 ms 21248 KB
ouh4 AC 101 ms 20608 KB
ouh5 AC 107 ms 23296 KB
ouh6 AC 105 ms 24064 KB
ouh7 AC 97 ms 20224 KB
ouh8 AC 108 ms 23296 KB
ouh9 AC 104 ms 24192 KB
same0 AC 107 ms 18304 KB
same1 AC 106 ms 18176 KB
same2 AC 103 ms 18432 KB
same3 AC 105 ms 18432 KB
same4 AC 100 ms 18048 KB
same5 AC 108 ms 18048 KB
same6 AC 103 ms 18176 KB
same7 AC 109 ms 18048 KB
same8 AC 101 ms 17920 KB
same9 AC 110 ms 18304 KB
sameline0 AC 112 ms 25856 KB
sameline1 AC 126 ms 26240 KB
sameline2 AC 113 ms 23936 KB
sameline3 AC 114 ms 24960 KB
sameline4 AC 111 ms 25856 KB
sameline5 AC 116 ms 25600 KB
sameline6 AC 110 ms 22912 KB
sameline7 AC 118 ms 26112 KB
sameline8 AC 113 ms 24320 KB
sameline9 AC 114 ms 23040 KB
star0 AC 85 ms 18676 KB
star1 AC 85 ms 18676 KB
star2 AC 84 ms 18676 KB
star3 AC 84 ms 18548 KB
star4 AC 85 ms 18676 KB
star5 AC 89 ms 18804 KB
star6 AC 85 ms 18804 KB
star7 AC 85 ms 18676 KB
star8 AC 87 ms 18548 KB
star9 AC 88 ms 18932 KB
supersmall0 AC 4 ms 10240 KB
supersmall1 AC 4 ms 10240 KB
supersmall2 AC 4 ms 10240 KB
supersmall3 AC 3 ms 10240 KB
supersmall4 AC 3 ms 10240 KB
supersmall5 AC 4 ms 10240 KB
supersmall6 AC 4 ms 10240 KB
supersmall7 AC 4 ms 10240 KB
supersmall8 AC 4 ms 10240 KB
supersmall9 AC 4 ms 10240 KB