Submission #23155

#	Time	Username	Problem	Language	Result	Execution time	Memory
23155		ainta	Logistical Metropolis (KRIII5_LM)	C++14	7 / 7	1193 ms	48572 KiB

LM

#include<cstdio>
#include<algorithm>
#include<vector>
#define pii pair<int,int>
using namespace std;
vector<int>E[101000], T[101000], L[101000];
int n, m, pL[101000][20], par[101000][18], Dep[101000], Num[101000], Ed[101000], cnt;
struct Edge{
    int a, b, c;
    bool operator <(const Edge &p)const{
        return c<p.c;
    }
}w[301000];
int UF[101000];
long long S;
int Find(int a){
    if(a==UF[a])return a;
    return UF[a] = Find(UF[a]);
}
bool Merge(int a, int b){
    a=Find(a),b=Find(b);
    if(a==b)return false;
    UF[a] = b;
    return true;
}
void DFS(int a, int pp){
    int i, x;
    Num[a] = ++cnt;
    for(i=0;i<17;i++){
        par[a][i+1]=par[par[a][i]][i];
        pL[a][i+1]=max(pL[a][i],pL[par[a][i]][i]);
    }
    for(i=0;i<T[a].size();i++){
        x = T[a][i];
        if(x==pp)continue;
        Dep[x] = Dep[a] + 1;
        par[x][0] = a;
        pL[x][0] = L[a][i];
        DFS(x,a);
    }
    Ed[a] = cnt;
}
vector<pii> V;
int LCA(int a, int b){
    if(Dep[a]<Dep[b])return LCA(b,a);
    int d = Dep[a]-Dep[b], i = 0;
    while(d){
        if(d&1)a = par[a][i];
        i++;d>>=1;
    }
    for(i=16;i>=0;i--)if(par[a][i]!=par[b][i])a=par[a][i],b=par[b][i];
    if(a!=b)a=par[a][0];
    return a;
}
int Cur;
vector<Edge>EE;
Edge Get(int a, int p){
    int d = Dep[a] - Dep[p], i = 0, M = 0, aa = a;
    while(d){
        if(d&1){
            M = max(M,pL[a][i]);
            a = par[a][i];
        }
        d>>=1;i++;
    }
    return {aa,p,M};
}
void Make(int a){
    int x = V[a].second;
    Cur++;
    while(1){
        if(Cur==V.size() || V[Cur].first > Ed[x])break;
        EE.push_back(Get(V[Cur].second,x));
        Make(Cur);
    }
}
long long GetMST(){
    int i;
    for(i=0;i<V.size();i++)UF[V[i].second] = V[i].second;
    long long ss = 0;
    for(i=0;i<EE.size();i++){
        if(Merge(EE[i].a,EE[i].b)){
            ss += EE[i].c;
        }
    }
    return ss;
}
void Do(int a, vector<int> &P){
    int i;
    vector<pii> TP;
    for(i=0;i<P.size();i++)TP.push_back({Num[P[i]],P[i]});
    sort(TP.begin(),TP.end());
    V = TP;
    for(i=0;i<TP.size()-1;i++){
        int x = LCA(TP[i].second, TP[i+1].second);
        V.push_back(pii(Num[x],x));
    }
    sort(V.begin(),V.end());
    V.erase(unique(V.begin(),V.end()),V.end());
    Cur = 0;
    Make(0);
    sort(EE.begin(),EE.end());
    long long s1 = GetMST() + E[a].size()* (long long)2e9;
    for(i=0;i<EE.size();i++)if(EE[i].c < 0)EE[i].c += 2e9;
    sort(EE.begin(),EE.end());
    long long s2 = GetMST();
    printf("%lld\n", S + s1 - s2);
}
int main(){
    int i, j;
    scanf("%d%d",&n,&m);
    for(i=1;i<=n;i++)UF[i] = i;
    for(i=0;i<m;i++){
        scanf("%d%d%d",&w[i].a,&w[i].b,&w[i].c);
    }
    sort(w,w+m);
    for(i=0;i<m;i++){
        E[w[i].a].push_back(i);
        E[w[i].b].push_back(i);
        if(Merge(w[i].a,w[i].b)){
            T[w[i].a].push_back(w[i].b);
            T[w[i].b].push_back(w[i].a);
            L[w[i].a].push_back(w[i].c);
            L[w[i].b].push_back(w[i].c);
            S += w[i].c;
        }
    }
    DFS(1, 0);
    for(i=1;i<=n;i++){
        vector<int>P;
        EE.clear();
        for(j=0;j<E[i].size();j++){
            Edge tp = w[E[i][j]];
            tp.c -= 2e9;
            EE.push_back(tp);
            P.push_back(tp.a+tp.b-i);
        }
        P.push_back(i);
        Do(i, P);
    }
}

Compilation message (stderr)

LM.cpp: In function 'void DFS(int, int)':
LM.cpp:33:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(i=0;i<T[a].size();i++){
              ^
LM.cpp: In function 'void Make(int)':
LM.cpp:72:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if(Cur==V.size() || V[Cur].first > Ed[x])break;
               ^
LM.cpp: In function 'long long int GetMST()':
LM.cpp:79:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(i=0;i<V.size();i++)UF[V[i].second] = V[i].second;
              ^
LM.cpp:81:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(i=0;i<EE.size();i++){
              ^
LM.cpp: In function 'void Do(int, std::vector<int>&)':
LM.cpp:91:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(i=0;i<P.size();i++)TP.push_back({Num[P[i]],P[i]});
              ^
LM.cpp:94:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(i=0;i<TP.size()-1;i++){
              ^
LM.cpp:104:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(i=0;i<EE.size();i++)if(EE[i].c < 0)EE[i].c += 2e9;
              ^
LM.cpp: In function 'int main()':
LM.cpp:132:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(j=0;j<E[i].size();j++){
                  ^
LM.cpp:111:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&n,&m);
                        ^
LM.cpp:114:48: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d%d",&w[i].a,&w[i].b,&w[i].c);
                                                ^

• Subtask 1: 2 / 2
• Subtask 2: 5 / 5