Submission #1126407

#	Time	Username	Problem	Language	Result	Execution time	Memory
1126407		luvna	Restore Array (RMI19_restore)	C++20	100 / 100	290 ms	1032 KiB

restore

#include<bits/stdc++.h>

#define MASK(i) (1 << (i))
#define pub push_back
#define all(v) v.begin(), v.end()
#define compact(v) v.erase(unique(all(v)), end(v))
#define pii pair<int,int>
#define fi first
#define se second
#define endl "\n"
#define sz(v) (int)(v).size()
#define dbg(x) "[" #x " = " << (x) << "]"

using namespace std;

template<class T> bool minimize(T& a, T b){if(a > b) return a = b, true;return false;}
template<class T> bool maximize(T& a, T b){if(a < b) return a = b, true;return false;}

typedef long long ll;
typedef long double ld;

mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rand(ll l, ll r){return uniform_int_distribution<ll>(l, r)(rng);}

const int N = 1e5 + 15;
const ll INF = 1e18;

int n, q;
int t[N], l[N], r[N], k[N];

namespace subtask1{
    bool check(void){
        return n <= 18 && q <= 200;
    }

    bool check(int mask){
        for(int j = 1; j <= q; j++){
            int cnt = 0;
            for(int i = l[j]; i <= r[j]; i++) cnt += ((mask >> i & 1) == t[j]);
            if(!t[j] && cnt < k[j]) return false;
            if(t[j] && cnt < (r[j] - l[j] + 1) - k[j] + 1) return false;
        }
        return true;
    }

    void main(){
        for(int mask = 0; mask < (1 << n); mask++){
            if(check(mask)){
                for(int i = 0; i < n; i++) cout << (mask >> i & 1) << " ";
                return;
            }
        }

        return cout << -1, void();
    }
}

namespace subtask4{
    /*
        dp[i] = number of zeros from 1 -> i
        dp[0] = 0 -> prefix sum
        base: 0 <= diff between dp[i-1] and dp[i] <= 1
    */

    struct edge{
        int u, v, w;
        edge() : u(0), v(0), w(0) {}
        edge(int u, int v, int w) : u(u), v(v), w(w) {}
        void get(int &U, int &V, int &W){
            U = u;
            V = v;
            W = w;
        }
    };

    ll dp[N];
    vector<edge> edges;

    void main(){
        //notes: detect negative cycle -> mul edge with -1

        for(int i = 1; i <= q; i++){
            l[i]++, r[i]++;
            // t = 0 -> at least k zeros from l -> r
            // dp[r] - dp[l-1] >= k
            // <=> dp[l-1] + k <= dp[r] -> create and edge (l-1, r, k)
            if(!t[i]) edges.push_back(edge(l[i]-1, r[i],-k[i]));
            // t = 1 -> zeros <= k-1
            // dp[r] - dp[l-1] <= k-1
            // dp[r] - k + 1 <= dp[l-1]
            else edges.push_back(edge(r[i],l[i]-1,k[i] - 1));
        }

        //base case: 0 <= dp[i] - dp[i-1] <= 1 -> create 2*n edges

        for(int i = 1; i <= n; i++){
            // low bound
            // dp[i] - dp[i-1] >= 0
            // dp[i-1] <= dp[i]
            edges.push_back(edge(i-1,i,0));
            // up bound
            // dp[i] - dp[i-1] <= 1
            // dp[i] - 1 <= dp[i-1]
            edges.push_back(edge(i,i-1,1));
        }

        fill(dp, dp + 1 + n, INF);

        dp[0] = INF;

        for(int turn = 0; turn < n; turn++){
            for(int i = 0; i < sz(edges); i++){
                int u, v, w; edges[i].get(u,v,w);
                minimize(dp[v], dp[u] + w);
            }
        }

        bool exist_neg_cycle = false;

        for(int i = 0; i < sz(edges); i++){
            int u, v, w; edges[i].get(u,v,w);
            if(dp[u] != INF && minimize(dp[v], dp[u] + w)){
                exist_neg_cycle = true;
                break;
            }
        }

        if(exist_neg_cycle) return cout << -1, void();

        for(int i = 1; i <= n; i++) cout << (dp[i] - dp[i-1] < 0 ? 0 : 1) << " ";
    }
}

void solve(){
    cin >> n >> q;

    for(int i = 1; i <= q; i++) cin >> l[i] >> r[i] >> k[i] >> t[i];

    /*if(subtask1::check()) subtask1::main();
    else*/ subtask4::main();
}

signed main(){
    ios_base::sync_with_stdio(NULL);
    cin.tie(0); cout.tie(0);

    #define task "task"

    if(fopen(task".INP", "r")){
        freopen(task".INP", "r", stdin);
        freopen(task".OUT", "w", stdout);
    }

    int t; t = 1; //cin >> t;
    while(t--) solve();
}

Compilation message (stderr)

restore.cpp: In function 'int main()':
restore.cpp:150:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  150 |         freopen(task".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
restore.cpp:151:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  151 |         freopen(task".OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 13 / 13
• Subtask 3: 25 / 25
• Subtask 4: 55 / 55