Submission #77857

#	Time	Username	Problem	Language	Result	Execution time	Memory
77857		duality	Pipes (CEOI15_pipes)	C++11	100 / 100	1506 ms	15036 KiB

pipes

#define DEBUG 0

#include <bits/stdc++.h>
using namespace std;

#if DEBUG
// basic debugging macros
int __i__,__j__;
#define printLine(l) for(__i__=0;__i__<l;__i__++){cout<<"-";}cout<<endl
#define printLine2(l,c) for(__i__=0;__i__<l;__i__++){cout<<c;}cout<<endl
#define printVar(n) cout<<#n<<": "<<n<<endl
#define printArr(a,l) cout<<#a<<": ";for(__i__=0;__i__<l;__i__++){cout<<a[__i__]<<" ";}cout<<endl
#define print2dArr(a,r,c) cout<<#a<<":\n";for(__i__=0;__i__<r;__i__++){for(__j__=0;__j__<c;__j__++){cout<<a[__i__][__j__]<<" ";}cout<<endl;}
#define print2dArr2(a,r,c,l) cout<<#a<<":\n";for(__i__=0;__i__<r;__i__++){for(__j__=0;__j__<c;__j__++){cout<<setw(l)<<setfill(' ')<<a[__i__][__j__]<<" ";}cout<<endl;}

// advanced debugging class
// debug 1,2,'A',"test";
class _Debug {
    public:
        template<typename T>
        _Debug& operator,(T val) {
            cout << val << endl;
            return *this;
        }
};
#define debug _Debug(),
#else
#define printLine(l)
#define printLine2(l,c)
#define printVar(n)
#define printArr(a,l)
#define print2dArr(a,r,c)
#define print2dArr2(a,r,c,l)
#define debug
#endif

// define
#define MAX_VAL 999999999
#define MAX_VAL_2 999999999999999999LL
#define EPS 1e-6
#define mp make_pair
#define pb push_back

// typedef
typedef unsigned int UI;
typedef long long int LLI;
typedef unsigned long long int ULLI;
typedef unsigned short int US;
typedef pair<int,int> pii;
typedef pair<LLI,LLI> plli;
typedef vector<int> vi;
typedef vector<LLI> vlli;
typedef vector<pii> vpii;
typedef vector<plli> vplli;

// ---------- END OF TEMPLATE ----------

int parent1[100000],parent2[100000];
int find(int n,int *parent) {
    if (parent[n] != n) parent[n] = find(parent[n],parent);
    return parent[n];
}
vpii adjList[100000];
int disc[100000],low[100000],num = 0;
int doDFS(int u,int p) {
    int i;
    disc[u] = low[u] = num++;
    for (i = 0; i < adjList[u].size(); i++) {
        int v = adjList[u][i].first;
        if (disc[v] == -1) {
            doDFS(v,adjList[u][i].second);
            low[u] = min(low[u],low[v]);
            if (low[v] > disc[u]) cout << u+1 << " " << v+1 << endl;
        }
        else if (adjList[u][i].second != p) low[u] = min(low[u],disc[v]);
    }
    return 0;
}
int main() {
    int i;
    int N,M,u,v;
    scanf("%d %d",&N,&M);
    for (i = 0; i < N; i++) parent1[i] = parent2[i] = i;
    for (i = 0; i < M; i++) {
        scanf("%d %d",&u,&v);
        u--,v--;
        int pu = find(u,parent1),pv = find(v,parent1);
        if (pu != pv) {
            parent1[pu] = pv;
            adjList[u].pb(mp(v,i));
            adjList[v].pb(mp(u,i));
        }
        else {
            pu = find(u,parent2),pv = find(v,parent2);
            if (pu != pv) {
                parent2[pu] = pv;
                adjList[u].pb(mp(v,i));
                adjList[v].pb(mp(u,i));
            }
        }
    }
    for (i = 0; i < N; i++) disc[i] = low[i] = -1;
    for (i = 0; i < N; i++) {
        if (disc[i] == -1) doDFS(i,-1);
    }

    return 0;
}

Compilation message (stderr)

pipes.cpp: In function 'int doDFS(int, int)':
pipes.cpp:68:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i = 0; i < adjList[u].size(); i++) {
                 ~~^~~~~~~~~~~~~~~~~~~
pipes.cpp: In function 'int main()':
pipes.cpp:82:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d",&N,&M);
     ~~~~~^~~~~~~~~~~~~~~
pipes.cpp:85:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d",&u,&v);
         ~~~~~^~~~~~~~~~~~~~~

• 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