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ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#638949 | #7177. Many Many Cycles | lichenyu_ac | RE | 0ms | 0kb | C++14 | 1.9kb | 2024-10-13 17:23:49 | 2024-10-13 17:23:49 |
answer
#include<bits/stdc++.h>
#define int long long
typedef long long ll;
using namespace std;
const int N=5e3+10,M=N*2;
int head[N],ver[M],nxt[M],tot=1;
ll edge[M];
void add(int x,int y,ll z){
ver[++tot]=y,edge[tot]=z,nxt[tot]=head[x],head[x]=tot;
}
tuple<int,int,ll>e[N],sta[N];
int fa[N],top;
int find(int x){
return fa[x]==x?x:fa[x]=find(fa[x]);
}
int n,m;
ll dis[N],dep[N],f[N][25],ans[N];
bool v[N];
void dfs(int x,int fa){
v[x]=1;
f[x][0]=fa;
for(int i=1;i<20;i++)
f[x][i]=f[f[x][i-1]][i-1];
for(int i=head[x];i;i=nxt[i]){
int y=ver[i];
if(y==fa)continue;
dep[y]=dep[x]+1,dis[y]=dis[x]+edge[i];
dfs(y,x);
}
}
int LCA(int x,int y){
if(dep[x]<dep[y])swap(x,y);
for(int i=19;~i;i--)
if(dep[f[x][i]]>=dep[y])
x=f[x][i];
if(x==y)return x;
for(int i=19;~i;i--)
if(f[x][i]!=f[y][i])
x=f[x][i],y=f[y][i];
return f[x][0];
}
ll dist(int x,int y){
return dis[x]+dis[y]-2*dis[LCA(x,y)];
}
ll gcd(ll a,ll b){
return b?gcd(b,a%b):a;
}
signed main(){
// freopen("test.in","r",stdin);
// freopen("test.out","w",stdout);
scanf("%d%d",&n,&m);
for(int i=1;i<=m;i++){
int x,y,z;
scanf("%d%d%d",&x,&y,&z);
e[i]=make_tuple(x,y,z);
}
for(int i=1;i<=n;i++)fa[i]=i;
for(int i=1;i<=m;i++){
auto [x,y,z]=e[i];
if(find(x)==find(y)){
sta[++top]=e[i];
}else{
fa[find(y)]=find(x);
add(x,y,z),add(y,x,z);
// printf("%d %d %lld\n",x,y,z);
}
}
for(int i=1;i<=n;i++)
if(!v[i])dep[i]=1,dfs(i,0);
for(int i=1;i<=top;i++){
auto [x,y,z]=sta[i];
ans[i]=z+dist(x,y);
}
ll tmp=ans[1];
for(int i=2;i<=top;i++)
tmp=gcd(tmp,ans[i]);
printf("%lld\n",tmp);
return 0;
}
Details
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Test #1:
score: 0
Runtime Error
input:
4 4 1 2 1 2 3 1 3 4 1 4 1 1