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ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#386029 | #7177. Many Many Cycles | xlao | WA | 0ms | 3980kb | C++14 | 1.6kb | 2024-04-11 11:12:41 | 2024-04-11 11:12:42 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int N=5005, M=1e4+5;
int n,m,bj[M];
struct Edge {int x,y,z;} e[M];
struct edge {int nex,to,v;} a[M<<1];
int h[N],tot=1;
void add(int x,int y,int z)
{
a[++tot]=(edge){h[x],y,z}, h[x]=tot;
a[++tot]=(edge){h[y],x,z}, h[y]=tot;
}
int sq[N<<1],in[N],ti; ll dep[N];
void dfs0(int u)
{
sq[in[u]=++ti]=u;
for(int i=h[u];i;i=a[i].nex) if(!in[a[i].to])
{
bj[i/2]=1;
int v=a[i].to;
dep[v]=dep[u]+a[i].v;
dfs0(v); sq[++ti]=u;
}
}
#define _min(x,y) (dep[x]<dep[y]?x:y)
int st[N<<1][15],lg[N<<1];
void build_ST()
{
lg[0]=-1; for(int i=1;i<=ti;++i) st[i][0]=sq[i], lg[i]=lg[i>>1]+1;
for(int i=1;(1<<i)<=ti;++i)
for(int l=1;l+(1<<i)-1<=ti;++l)
st[l][i] = _min(st[l][i-1], st[l+(1<<(i-1))][i-1]);
}
int LCA(int x,int y)
{
x=in[x], y=in[y];
if(x>y) swap(x,y);
int k=lg[y-x+1];
return _min(st[x][k], st[y-(1<<k)+1][k]);
}
int main()
{
scanf("%d %d",&n,&m);
for(int i=1,x,y,z;i<=m;++i)
scanf("%d %d %d",&x,&y,&z), add(x,y,z), e[i]=(Edge){x,y,z};
dfs0(1);
build_ST();
ll ans=0;
for(int i=1;i<=m;++i) if(!bj[i])
{
int u=e[i].x, v=e[i].y, w=e[i].z;
if(dep[u]<dep[v]) swap(u,v);
if(!ans) ans = dep[u]-dep[v]+w;
else ans = __gcd(ans, dep[u]-dep[v]+w);
for(int j=i+1;j<=m;++j) if(!bj[j])
{
int x=e[j].x, y=e[j].y, z=e[j].z;
if(dep[x]<dep[y]) swap(x,y);
if(LCA(u,y)==y)
{
int dw=LCA(u,x), up=LCA(v,y);
ans = __gcd(ans, dep[u]-dep[v]+w + dep[x]-dep[y]+z - (dep[dw]-dep[up])*2);
}
}
}
printf("%lld\n",ans);
}
詳細信息
Test #1:
score: 100
Accepted
time: 0ms
memory: 3964kb
input:
4 4 1 2 1 2 3 1 3 4 1 4 1 1
output:
4
result:
ok answer is '4'
Test #2:
score: 0
Accepted
time: 0ms
memory: 3968kb
input:
4 5 1 2 1 1 3 2 1 4 1 2 3 1 3 4 1
output:
4
result:
ok answer is '4'
Test #3:
score: 0
Accepted
time: 0ms
memory: 3980kb
input:
20 50 1 2 8 1 3 1 3 4 5 3 5 9 3 6 5 6 7 6 7 8 8 2 9 2 8 10 3 8 11 7 8 12 5 3 13 4 7 14 3 6 15 7 9 16 6 8 17 7 16 18 9 16 19 3 18 20 10 11 3 2 17 1 1 16 2 2 15 1 1 10 3 2 9 1 2 19 2 1 6 1 2 7 3 1 17 3 2 15 3 2 8 6 2 5 1 2 8 1 2 12 1 1 12 7 1 4 1 2 18 2 1 11 7 1 14 1 1 18 1 1 18 9 1 10 6 1 14 3 2 20 2...
output:
2
result:
ok answer is '2'
Test #4:
score: -100
Wrong Answer
time: 0ms
memory: 3960kb
input:
20 50 1 2 18468 1 3 26501 3 4 15725 3 5 29359 3 6 24465 6 7 28146 7 8 16828 2 9 492 8 10 11943 8 11 5437 8 12 14605 3 13 154 7 14 12383 6 15 18717 9 16 19896 8 17 21727 16 18 11539 16 19 19913 18 20 26300 11 3 2 17 1 1 16 2 2 15 1 1 10 3 2 9 1 2 19 2 1 6 1 2 7 3 1 17 3 2 15 3 2 8 6 2 5 1 2 8 1 2 12 ...
output:
-1
result:
wrong answer expected '1', found '-1'