Submission #893371

#	Time	Username	Problem	Language	Result	Execution time	Memory
893371		karrigan	Airplane (NOI23_airplane)	C++14	100 / 100	315 ms	23972 KiB

Main

#include<bits/stdc++.h>
using namespace std;
#define all(fl) fl.begin(),fl.end()
#define pb push_back
#define fi first
#define se second
#define for1(i,j,k) for(int i=j;i<=k;i++)
#define for2(i,j,k) for(int i=j;i>=k;i--)
#define for3(i,j,k,l) for(int i=j;i<=k;i+=l)
#define lb lower_bound
#define ub upper_bound
#define sz(a) (int)a.size()
#define pii pair<int,int>
#define pli pair<long long,int>
#define gcd __gcd
#define lcm(x,y) x*y/__gcd(x,y)
#define lastbit(i) __builtin_ctz(i)
#define pil pair<int,long long>
const int maxn=2e5+9;
const long long inf=1e15;
long long b[maxn];
vector<int>a[maxn];
int n;
struct cus{
int u;
long long val;
bool operator < (const cus &p)const {
return val>p.val;
}
};
vector<long long> cal(int s){
vector<long long>f(n+1);
vector<bool>vis(n+1);
for1(i,1,n)f[i]=inf;
f[s]=0;
priority_queue<cus>t;
t.push({s,0});
while (!t.empty()){
    auto u=t.top();
    t.pop();
    if (vis[u.u])continue;
    vis[u.u]=1;
    for (auto v:a[u.u]){
    if (f[v]>max(b[v],f[u.u]+1)){
    f[v]=max(b[v],f[u.u]+1);
    t.push({v,f[v]});
    }
    }
}
return f;
}
long long ans[maxn];
signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    //freopen("temp.INP","r",stdin);
    //freopen("temp.OUT","w",stdout);
    int m;
    cin>>n>>m;
    for1(i,1,n)cin>>b[i];
    for1(i,1,m){
    int u,v;
    cin>>u>>v;
    a[u].pb(v);
    a[v].pb(u);
    }
    vector<long long>tmp=cal(1);
    for1(i,1,n){
    ans[i]+=tmp[i];
    }
    tmp=cal(n);
    long long vcl=inf;
    for1(i,1,n){
    if (abs(ans[i]-tmp[i])<=1)vcl=min(vcl,ans[i]+tmp[i]);
    }
    cout<<vcl;
}

• Subtask 1: 22 / 22
• Subtask 2: 10 / 10
• Subtask 3: 31 / 31
• Subtask 4: 37 / 37