/******************************
* author : @hihihihi *
* date : 02 / 12 / 2022 *
******************************/
#include <bits/stdc++.h>
// #pragma GCC optimize("O2")
// #pragma GCC target("avx,avx2,fma")
// #pragma GCC optimize ("O3,unroll-loops,no-stack-protector")
// #pragma GCC target ("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
// template
#define PB push_back
#define ALL(i_) i_.begin(), i_.end()
#define LOG2(x_) (31 - __builtin_clz(x_))
#define getBit(x_, i_) ((x_ >> i_) & (ll) 1)
#define rd(l_, r_) (l_ + rng() % (r_ - l_ + 1))
#define FOR(i_, a_, b_) for(int i_ = (int) (a_); i_ <= (int) (b_); ++i_)
#define FORD(i_, a_, b_) for(int i_ = (int) (a_); i_ >= (int) (b_); --i_)
// debugger
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef DEBUG
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif
typedef long long ll;
typedef long double ld;
template<class X, class Y> bool minimize(X &x, const Y &y){
X eps = 1e-9;
if (x > y + eps) {
x = y;
return 1;
}
return 0;
}
template<class X, class Y> bool maximize(X &x, const Y &y) {
X eps = 1e-9;
if (x + eps < y) {
x = y;
return 1;
}
return 0;
}
template<class T> T Abs(const T &x) { return (x < 0 ? -x : x); }
template<class T> using heap_min = priority_queue<T, vector<T>, greater<T>>;
template<class T> using heap_max = priority_queue<T>;
const int mod = (int) 1e9 + 7;
template<class X, class Y> void Add(X &x, const Y &y){
x += y;
if(x >= mod) x -= mod;
if(x < 0) x += mod;
}
const int oo = (int) 1e9 + 99;
const array<int, 2> dxy8[] = { {-1, 0}, {1, 0}, {0, 1}, {0, -1}, {1, -1}, {1, 1}, {-1, 1}, {-1, -1} };
const array<int, 2> dxy4[] = { {-1, 0}, {1, 0}, {0, 1}, {0, -1} };
const int maxn = (int) 1e5 + 11;
const int LOG = (int) LOG2(maxn) + 3;
void File(){
#define TASK "CIJANOBAKTERIJE"
if(fopen(TASK".inp", "r")) {
freopen(TASK".inp", "r", stdin);
freopen(TASK".out", "w", stdout);
}
}
int n, m;
vector<int> adj[maxn];
void ReadInput(){
cin >> n >> m;
FOR(i, 1, m){
int u, v; cin >> u >> v;
adj[u].PB(v);
adj[v].PB(u);
}
}
int cnt = 1;
int vs[maxn], in[maxn], out[maxn];
int child[3][maxn];
void DFS_IN(int u = 1, int par = -1){
vs[u] = cnt;
child[1][u] = child[2][u] = INT_MIN;
for(int v : adj[u]) if(v != par && !vs[v]){
DFS_IN(v, u);
maximize(in[u], in[v] + 1);
if(in[v] > child[1][u]){
child[2][u] = child[1][u];
child[1][u] = in[v];
}
else if(in[v] > child[2][u]) child[2][u] = in[v];
}
}
void DFS_OUT(int u = 1, int par = -1){
if(par != -1){
out[u] = out[par] + 1;
if(in[u] == child[1][par]){
maximize(out[u], child[2][par] + 2);
}
else{
maximize(out[u], child[1][par] + 2);
}
}
for(int v : adj[u]) if(v != par) DFS_OUT(v, u);
}
int f[maxn];
void Solve(){
FOR(i, 1, n) if(!vs[i]){
DFS_IN(i);
DFS_OUT(i);
++cnt;
}
FOR(i, 1, n){
f[vs[i]] = max(in[i], out[i]) + 1;
}
int res = 0;
FOR(i, 1, cnt) res += f[i];
cout << res;
}
int main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
File();
ReadInput();
Solve();
cerr << "\nTime elapsed: " << 1000.0 * clock() / CLOCKS_PER_SEC << " ms.\n";
return 0;
}
Compilation message
Main.cpp: In function 'void File()':
Main.cpp:93:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
93 | freopen(TASK".inp", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:94:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
94 | freopen(TASK".out", "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
3540 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
33 ms |
15900 KB |
Output is correct |
| 2 |
Correct |
6 ms |
3460 KB |
Output is correct |
| 3 |
Correct |
7 ms |
4356 KB |
Output is correct |
| 4 |
Correct |
9 ms |
5124 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
2688 KB |
Output is correct |
| 2 |
Correct |
2 ms |
2644 KB |
Output is correct |
| 3 |
Correct |
2 ms |
2644 KB |
Output is correct |
| 4 |
Correct |
2 ms |
2772 KB |
Output is correct |
| 5 |
Correct |
5 ms |
3540 KB |
Output is correct |
| 6 |
Correct |
8 ms |
4436 KB |
Output is correct |
| 7 |
Correct |
10 ms |
5332 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
2644 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
3540 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
