CSES - Practice Contest 2024 - Results
Submission details
Task:Graph painting
Sender:oneofususespy
Submission time:2024-09-28 16:55:44 +0300
Language:C++ (C++20)
Status:READY
Result:
Test results
testverdicttime
#10.01 sdetails
#2ACCEPTED0.01 sdetails
#3ACCEPTED0.14 sdetails

Code

#ifdef ONPC
#define _GLIBCXX_DEBUG
#endif
#include <bits/stdc++.h>
#define char unsigned char
#define rep(i, a, b) for(int i=a; i< (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
#define eb emplace_back
#define mp make_pair
#define mt make_tuple
#define fi first
#define se second
#define pb push_back
#define LSOne(S) ((S) & -(S))
using namespace std;
// mt19937 rnd(239);
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
typedef long long C;
typedef complex<C> P;
#define X real()
#define Y imag()
template<class T>
istream& operator>> (istream& is, complex<T>& p) {
T value;
is >> value;
p.real(value);
is >> value;
p.imag(value);
return is;
}
typedef long long ll;
typedef long double ld;
using pi = pair<ll, ll>;
using vi = vector<ll>;
template <class T>
using pq = priority_queue<T>;
template <class T>
using pqg = priority_queue<T, vector<T>, greater<T>>;
int popcnt(int x) { return __builtin_popcount(x); }
int popcnt(ll x) { return __builtin_popcountll(x); }
#define MIN(v) *min_element(all(v))
#define MAX(v) *max_element(all(v))
#define LB(c, x) distance((c).begin(), lower_bound(all(c), (x)))
#define UB(c, x) distance((c).begin(), upper_bound(all(c), (x)))
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...);}
#ifdef DEBUG
#define dbg(x...) cerr << "\e[91m"<<__func__<<":"<<__LINE__<<" [" << #x << "] = ["; _print(x); cerr << "\e[39m" << endl;
#else
#define dbg(x...)
#endif
template<typename S, typename T = S> void chmin(S &s, T t) {s = s < t ? s : t;}
template<typename S, typename T = S> void chmax(S &s, T t) {s = s > t ? s : t;}
const int INF = 1e9; // 10^9 = 1B is < 2^31-1
const ll LLINF = 4e18; // 4*10^18 is < 2^63-1
const double EPS = 1e-9;
const ll MOD = 1e9+7;
const int N=2e5+10;
vector<int> adj[N];
int color[N]; // 0-RED, 1-BLUE
bool vis[N];
int n,m;
bool verify() {
int cnt=0;
for (int i = 1; i <= n; i++) {
for(auto &w:adj[i]) {
if(color[w]!=color[i]) cnt++;
}
}
return cnt/2>=m/2;
}
int noColCnt[N];
int solve() {
std::cin >> n >> m;
for (int i = 1; i <= n; i++) {
adj[i].clear();
color[i]=-1;
vis[i]=false;
noColCnt[i]=0;
}
for (int i = 0; i < m; i++) {
int a,b; std::cin >> a >> b;
adj[a].pb(b);
adj[b].pb(a);
noColCnt[a]++;
noColCnt[b]++;
}
priority_queue<pair<int,int>> pq;
for (int i = 1; i <= n; i++) {
pq.push({(int)adj[i].size(), i});
}
//return 0;
while(!pq.empty()) {
pair<int,int> e=pq.top();
pq.pop();
if(noColCnt[e.se]!=e.fi) {
pq.push({noColCnt[e.se], e.se});
continue;
}
//__print(e); std::cout << std::endl;
int i=e.se;
//for (int i = 1; i <= n; i++) {
if(color[i]!=-1 || vis[i]) continue;
queue<int> q;
q.push(i);
color[i]=0;
for(auto &w:adj[i]) {
noColCnt[w]--;
}
//while(!q.empty()) {
//int curr=q.front();
//q.pop();
//if(vis[curr]) {
//continue;
//}
//vis[curr]=true;
//
vis[i]=true;
//
//int cntDiff=0, nonSet=0;
//for(auto &w:adj[curr]) {
//if(color[w]!=-1 && color[w]!=color[curr]) cntDiff++;
//else if(color[w]==-1) nonSet++;
//}
//std::cout << cntDiff << " " << nonSet << " out of " << adj[curr].size() << std::endl;
//std::cout << "need at least: " << adj[curr].size()/2 << std::endl;
//int todoDiff=(int)adj[curr].size()/2-cntDiff;
//std::cout << "need diff still: " << todoDiff << std::endl;
//assert(nonSet>=todoDiff);
/*
for(auto &w:adj[curr]) {
if(color[w]==-1) {
color[w]=1-color[curr];
if(!vis[w]) q.push(w);
}
}
*/
for(auto &w:adj[i]) {
if(color[w]==-1) {
color[w]=1-color[i];
noColCnt[i]--;
}
}
//std::cout << std::endl;
//}
}
for (int i = 1; i <= n; i++) {
assert(color[i]!=-1);
if(color[i]==0) {
std::cout << "B ";
} else if(color[i]==1) {
std::cout << "R ";
}
}
std::cout << std::endl;
//assert(verify());
return 0;
}
int32_t main() {
ios::sync_with_stdio(0);
cin.tie(0);
int TET = 1;
cin >> TET;
for (int i = 1; i <= TET; i++) {
#ifdef ONPC
#endif
if (solve()) {
break;
}
#ifdef ONPC
#endif
}
#ifdef ONPC
cerr << endl << "finished in " << clock() * 1.0 / CLOCKS_PER_SEC << " sec" << endl;
#endif
}

Test details

Test 1

Verdict:

input
100
7 1
2 5
8 28
2 7
...

correct output
B R B B B B R 
R B B R B R B B 
R R B B B B R R R B 
B B R B R B 
B B B R B R R B R 
...

user output
B R B B B B B 
R R R R R R R B 
R R R B B R R R B R 
R R R R R B 
R B R R R R B R R 
...
Truncated

Test 2

Verdict: ACCEPTED

input
10
38 36
18 28
20 37
22 38
...

correct output
R R B R B R R R R R B B R B R ...

user output
B B R R B B B B B R B R B B B ...
Truncated

Test 3

Verdict: ACCEPTED

input
1
100000 200000
89300 98492
33853 56822
92967 99427
...

correct output
R R R R B R R R B B B R B B B ...

user output
B B B R R R B R R R R B R B R ...
Truncated