Submission #1276938

#	Time	Username	Problem	Language	Result	Execution time	Memory
1276938		minhvule	여별 열쇠 (JOI15_keys)	C++20	100 / 100	2 ms	1344 KiB

keys

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

#define int long long
#define task "task"
#define fi first
#define se second
#define pb push_back
#define FOR(i, a, b) for(int i = (a), _b = (b); i <= _b; i ++)
#define FORD(i, a, b) for(int i = (a), _b = (b); i >= _b; i --)
#define bit(x, i) ((x >> i) & 1)
#define oo 1e18
#define all(v) v.begin(), v.end()

using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;
// mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
// ll rand(ll l, ll r) { assert(l <= r); return uniform_int_distribution<ll>(l, r)(rd); }
const int N = 2e3 + 5;
const int mod = 1e9 + 7;
const int base = 31;
int n, m, k, dp[N][N][2], val[N], ans = 0, sz[N], f[N];
vector<pii> g[N];
vector<pii> v;
bool vis[N];
void dfs(int u, int p){
    sz[u] = vis[u] = 1;
    dp[u][1][1] = val[u];
    for(auto [v, w] : g[u]) if(v != p){
        dfs(v, u);
        FORD(i, sz[u], 0)
            FOR(j, 1, min(sz[v], k - i)){
                dp[u][i + j][0] = max(dp[u][i + j][0], dp[u][i][0] + max(dp[v][j][0], dp[v][j][1])); 
                if(i > 0) dp[u][i + j][1] = max({dp[u][i + j][1], dp[u][i][1] + dp[v][j][0], dp[u][i][1] + dp[v][j][1] + w});
            }
        sz[u] += sz[v];
    }
}
void solve(){
    cin>>n>>m>>k;
    FOR(i, 1, n){
        int x, y; cin>>x>>y;
        v.pb({x, i});
        v.pb({y, -i});
    }
    sort(v.begin(), v.end());
    FOR(i, 1, v.size() - 1){
        int len = v[i].fi - v[i - 1].fi;
        if(v[i - 1].se > 0 && v[i].se > 0) val[v[i - 1].se] += len;
        if(v[i - 1].se < 0 && v[i].se < 0) val[-v[i].se] += len;
        if(v[i - 1].se > 0 && v[i].se < 0){
            int x = -v[i].se, y = v[i - 1].se;
            if(x == y){
                val[x] += len;
                continue;
            }
            g[x].pb({y, len});
            g[y].pb({x, len});
        }
        if(v[i - 1].se < 0 && v[i].se > 0)
            ans += len;
    }
    FOR(i, 1, n) if(!vis[i]){
        dfs(i, 0);
        FORD(j, k, 0)
            FOR(o, 1, sz[i])
                f[j + o] = max(f[j + o], f[j] + max(dp[i][o][0], dp[i][o][1]));
    }
    cout<<ans + f[k] + m - v[v.size() - 1].fi + v[0].fi;
}
signed main(){
    ios::sync_with_stdio(false);
    cin.tie(NULL);
    if(fopen(task".inp", "r")){
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    int nTest = 1;
    // cin>>nTest;
    while(nTest --) solve();
    // cerr << "\nTime: " << 1.0 * clock() / CLOCKS_PER_SEC << "s\n";
    return 0;
}
/*



*/

Compilation message (stderr)

keys.cpp: In function 'int main()':
keys.cpp:76:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   76 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
keys.cpp:77:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   77 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 90 / 90