Submission #32825

#	Time	Username	Problem	Language	Result	Execution time	Memory
32825		imaxblue	Pipes (CEOI15_pipes)	C++14	100 / 100	2678 ms	15596 KiB

pipes

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define mp make_pair
#define pb push_back
#define x first
#define y second
#define pii pair<int, int>
#define p3i pair<pii, int>
#define pll pair<ll, ll>
#define p3l pair<pll, ll>
#define lseg L, (L+R)/2, N*2+1
#define rseg (L+R)/2+1, R, N*2+2
#define ub upper_bound
#define lb lower_bound
#define pq priority_queue
#define MN 1000000007
#define fox(k, x) for (int k=0; k<x; ++k)
#define fox1(k, x) for (int k=1; k<=x; ++k)
#define foxr(k, x) for (int k=x-1; k>=0; --k)
#define fox1r(k, x) for (int k=x; k>0; --k)
#define ms multiset
#define flood(x) memset(x, 0x3f3f3f3f, sizeof x)
#define drain(x) memset(x, 0, sizeof x)
#define rng() (rand() >> 3)*rand()

int n, m, t, a, b, r[100005], p[100005], h[100005], d[100005];
bool u[100005];
vector<int> v[100005], com[100005];
bool mrg(int A, int B){
    //cout << A << ' ' << B << ' ' ;
    A=r[A]; B=r[B];
    //cout << A << ' ' << B << ' ' << endl;
    if (A==B) return 0;
    if (com[A].size()<com[B].size()) return mrg(B, A);
    for (auto i:com[B]){
        com[A].pb(i);
        r[i]=A;
    }
    return 1;
}
void dfs(int N, int P){
    p[N]=P;
    if (P!=-1) d[N]=d[P]+1;
    fox(l, v[N].size()){
        if (v[N][l]==P) continue;
        dfs(v[N][l], N);
    }
}
void lca(int X, int Y){
    X=r[X]; Y=r[Y];
    //int C=0;
    while(X!=Y){
        //fox(l, com[X].size()) cout << com[X][l] << ' '; cout << endl;
        //fox(l, com[Y].size()) cout << com[Y][l] << ' '; cout << endl;
        //C++;
        //if (C>5) return;
        if (d[h[X]]>d[h[Y]]){
            u[h[X]]=1;
            t=h[r[p[h[X]]]];
            mrg(X, p[h[X]]);
            h[X]=t;
            //X=p[X];
        } else {
            u[h[Y]]=1;
            //Y=p[Y];
            t=h[r[p[h[Y]]]];
            mrg(Y, p[h[Y]]);
            h[Y]=t;
        }
        X=r[X]; Y=r[Y];
        //cout << X << ' ' << h[X] << ' ' << Y << ' ' << h[Y]<< endl;

    }
}
queue<pii> q;
int main(){
    scanf("%i%i", &n, &m);
    fox1(l, n){
        r[l]=l; h[l]=l;
        com[l].clear(); com[l].pb(l);
    }
    fox(l, m){
        scanf("%i%i", &a, &b);
        if (mrg(a, b)){
            //cout << l << endl;
            v[a].pb(b);
            v[b].pb(a);
            q.push(mp(a, b));
        }
    }
    fox1(l, n){
        if (p[l]==0){
            dfs(l, -1);
        }
    }
    //return 00;
    fox1(l, n){
        r[l]=l;
        com[l].clear(); com[l].pb(l);
    }
    rewind(stdin);
    scanf("%i%i", &n, &m);
    fox(l, m){
        scanf("%i%i", &a, &b);
        if (mp(a, b)==q.front()) q.pop();
        else lca(a, b);
    }
    fox1(l, n){
        if (!u[l] && p[l]!=-1){
            printf("%i %i\n", l, p[l]);
        }
    }
    return 0;
}

Compilation message (stderr)

pipes.cpp: In function 'void dfs(int, int)':
pipes.cpp:18:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define fox(k, x) for (int k=0; k<x; ++k)
pipes.cpp:45:9:
     fox(l, v[N].size()){
         ~~~~~~~~~~~~~~            
pipes.cpp:45:5: note: in expansion of macro 'fox'
     fox(l, v[N].size()){
     ^~~
pipes.cpp: In function 'int main()':
pipes.cpp:78:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%i%i", &n, &m);
     ~~~~~^~~~~~~~~~~~~~~~
pipes.cpp:84:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%i%i", &a, &b);
         ~~~~~^~~~~~~~~~~~~~~~
pipes.cpp:103:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%i%i", &n, &m);
     ~~~~~^~~~~~~~~~~~~~~~
pipes.cpp:105:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%i%i", &a, &b);
         ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10