Submission #32814

#	Time	Username	Problem	Language	Result	Execution time	Memory
32814		imaxblue	Pipes (CEOI15_pipes)	C++14	30 / 100	5093 ms	13304 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, a, b, r[100005], p[100005], d[100005];
bool u[100005];
vector<int> v[100005], com[100005];
bool mrg(int A, int B){
    A=r[A]; B=r[B];
    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];
    if (p[X]!=-1 && r[p[X]]==Y || p[Y]!=-1 && r[p[Y]]==X) return;
    while(X!=Y){
        if (d[X]>d[Y]){
            u[X]=1;
            X=r[p[X]];
        } else {
            u[Y]=1;
            Y=r[p[Y]];
        }
    }
}
int main(){
    scanf("%i%i", &n, &m);
    fox1(l, n){
        r[l]=l;
        com[l].clear(); com[l].pb(l);
    }
    fox(l, m){
        scanf("%i%i", &a, &b);
        if (mrg(a, b)){
            v[a].pb(b);
            v[b].pb(a);
        }
    }
    fox1(l, n){
        if (p[l]==0){
            dfs(l, -1);
        }
    }
    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);
        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:43:9:
     fox(l, v[N].size()){
         ~~~~~~~~~~~~~~            
pipes.cpp:43:5: note: in expansion of macro 'fox'
     fox(l, v[N].size()){
     ^~~
pipes.cpp: In function 'void lca(int, int)':
pipes.cpp:50:18: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     if (p[X]!=-1 && r[p[X]]==Y || p[Y]!=-1 && r[p[Y]]==X) return;
         ~~~~~~~~~^~~~~~~~~~~~~
pipes.cpp: In function 'int main()':
pipes.cpp:62:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%i%i", &n, &m);
     ~~~~~^~~~~~~~~~~~~~~~
pipes.cpp:68:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%i%i", &a, &b);
         ~~~~~^~~~~~~~~~~~~~~~
pipes.cpp:84:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%i%i", &n, &m);
     ~~~~~^~~~~~~~~~~~~~~~
pipes.cpp:86:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%i%i", &a, &b);
         ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10