oj.uz

Submission #132982

# Submission time Handle Problem Language Result Execution time Memory
132982 2019-07-20T03:25:37 Z ae04071 Duathlon (APIO18_duathlon) C++11
0 / 100
 130 ms 22356 KB 
#include <bits/stdc++.h>
using namespace std;

int n,m,cut[100001],dfn[100001],low[100001],o,dn;
int bsz[200001];
vector<int> adj[100001],badj[200001];
stack<int> stk;

int ts;
void addEdge(int u,int v) {
    badj[u].push_back(v);
    badj[v].push_back(u);
}
void dfs(int cur,int p,int root=0) {
    ts++;
    dfn[cur] = low[cur] = ++dn;
    stk.push(cur);

    int c=0;
    for(auto &it:adj[cur]) if(it!=p) {
        if(dfn[it]) low[cur] = min(low[cur],low[it]);
        else {
            dfs(it,cur);
            low[cur] = min(low[cur],low[it]);
            if(low[it]>=dfn[cur]) {
                if(root && !c) {
                    c=1; continue;
                }
                ++n;
                cut[cur] = 1;
                while(!stk.empty()) {
                    int v=stk.top();
                    bsz[n]++;
                    if(cut[v]) addEdge(n, v);
                    if(v==cur) break;
                    stk.pop();
                }
            }
        }
    }
    if(root && c>1) {
        ++n;
        cut[cur] = 1;
        while(!stk.empty()) {
            int v=stk.top();
            bsz[n]++;
            if(cut[v]) addEdge(n, v);
            if(v==cur) break;
            stk.pop();
        }
    }
}

long long ans;
int sz[200001];
int cal_dfs(int cur,int p) {
    sz[cur] = bsz[cur];
    for(auto &it:badj[cur]) if(it!=p) sz[cur] += cal_dfs(it,cur);
    sz[cur] -= ((int)badj[cur].size() - (p>0) - (cur<=o));

    if(cur>o) {
        for(auto &it:badj[cur]) if(it!=p) ans += 1ll*(bsz[cur]-1)*sz[it]*(sz[it]-1);
        ans += 1ll*(bsz[cur]-1)*(ts-sz[cur]+1)*(ts-sz[cur]);
    }
    return sz[cur];
}

int main() {
    scanf("%d%d",&n,&m);
    for(int i=0,u,v;i<m;i++) {
        scanf("%d%d",&u,&v);
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    o = n;

    long long ret = 0;
    for(int i=1;i<=o;i++) if(!dfn[i]) {
        ts=0; ans=0;
        dfs(i,0,1);
        while(!stk.empty()) stk.pop();
        
        cal_dfs(i, 0);
        ret += 1ll*ts*(ts-1)*(ts-2) - ans;
    }
    printf("%lld\n",ret);
    
    return 0;
}

Compilation message

count_triplets.cpp: In function 'int main()':
count_triplets.cpp:69:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&n,&m);
     ~~~~~^~~~~~~~~~~~~~
count_triplets.cpp:71:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d",&u,&v);
         ~~~~~^~~~~~~~~~~~~~

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 7416 KB Output is correct
2 Correct 8 ms 7416 KB Output is correct
3 Correct 8 ms 7416 KB Output is correct
4 Correct 8 ms 7416 KB Output is correct
5 Correct 8 ms 7416 KB Output is correct
6 Correct 8 ms 7416 KB Output is correct
7 Incorrect 8 ms 7544 KB Output isn't correct
8 Halted 0 ms 0 KB -

Subtask #2
0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 7416 KB Output is correct
2 Correct 8 ms 7416 KB Output is correct
3 Correct 8 ms 7416 KB Output is correct
4 Correct 8 ms 7416 KB Output is correct
5 Correct 8 ms 7416 KB Output is correct
6 Correct 8 ms 7416 KB Output is correct
7 Incorrect 8 ms 7544 KB Output isn't correct
8 Halted 0 ms 0 KB -

Subtask #3
0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 99 ms 21248 KB Output is correct
2 Correct 101 ms 21136 KB Output is correct
3 Incorrect 127 ms 22356 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #4
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 9 ms 7544 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 13.0

# Verdict Execution time Memory Grader output
1 Incorrect 130 ms 17824 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #6
0 / 15.0

# Verdict Execution time Memory Grader output
1 Incorrect 9 ms 7544 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #7
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 118 ms 17060 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #8
0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 7416 KB Output is correct
2 Correct 8 ms 7416 KB Output is correct
3 Correct 8 ms 7416 KB Output is correct
4 Correct 8 ms 7416 KB Output is correct
5 Correct 8 ms 7416 KB Output is correct
6 Correct 8 ms 7416 KB Output is correct
7 Incorrect 8 ms 7544 KB Output isn't correct
8 Halted 0 ms 0 KB -

Subtask #9
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 7416 KB Output is correct
2 Correct 8 ms 7416 KB Output is correct
3 Correct 8 ms 7416 KB Output is correct
4 Correct 8 ms 7416 KB Output is correct
5 Correct 8 ms 7416 KB Output is correct
6 Correct 8 ms 7416 KB Output is correct
7 Incorrect 8 ms 7544 KB Output isn't correct
8 Halted 0 ms 0 KB -