Submission #578562

#	Time	Username	Problem	Language	Result	Execution time	Memory
578562		InternetPerson10	Copy and Paste 3 (JOI22_copypaste3)	C++17	25 / 100	3074 ms	195988 KiB

copypaste3

#include <bits/stdc++.h>
typedef long long ll;

using namespace std;

ll ans[2501][2501];

int n;
string s;
ll a, b, c;

map<string, int> ma;
vector<vector<int>> apps;
vector<vector<int>> ne;
vector<vector<vector<int>>> lift;
vector<int> siz;

ll f(int x, int y) {
    if(ans[x][y] != -1) return ans[x][y];
    if(y - x == 1) {
        return ans[x][y] = a;
    }
    ll best = f(x, y-1) + a;
    for(int i = x + (y - x + 1) / 2; i < y; i++) {
        if(a * (y - i) < c) break;
        int str_idx = ma[s.substr(i, y-i)];
        int l = 0, r = apps[str_idx].size();
        while(l != r - 1) {
            int mid = (l + r) / 2;
            if(apps[str_idx][mid] <= i) l = mid;
            else r = mid;
        }
        assert(apps[str_idx][l] == i);
        int ctApps = 1;
        // Optimize with binary lifting if this is right
        /*
        while(apps[str_idx][l] >= x) {
            ctApps++;
            l = ne[str_idx][l];
            if(l == -1) break;
        }
        */
        // Optimized
        for(int i = 12; i >= 0; i--) {
            int tent = lift[str_idx][l][i];
            if(tent != -1) {
                if(apps[str_idx][tent] >= x) {
                    l = tent;
                    ctApps += (1 << i);
                }
            }
        }
        int indivChars = y - x - ctApps * (y - i);
        best = min(best, f(i, y) + b + a * indivChars + c * ctApps);
    }
    return ans[x][y] = best;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> s >> a >> b >> c;
    for(int i = 0; i <= n; i++) {
        for(int j = 0; j <= n; j++) {
            ans[i][j] = -1;
        }
    }
    for(int i = 0; i < n; i++) {
        for(int j = i+1; j <= n; j++) {
            string s2 = s.substr(i, j-i);
            if(!ma.count(s2)) {
                ma[s2] = ma.size();
                apps.push_back(vector<int>());
                siz.push_back(j-i);
            }
            apps[ma[s2]].push_back(i);
        }
    }
    ne = apps;
    lift.resize(ne.size());
    for(int j = 0; j < ne.size(); j++) {
        lift[j].resize(ne[j].size());
        vector<int> v = ne[j];
        queue<int> q;
        for(int i = v.size() - 1; i >= 0; i--) {
            q.push(i);
            int g = q.front();
            while(v[g] - v[i] >= siz[j]) {
                q.pop();
                ne[j][g] = i;
                g = q.front();
            }
        }
        while(q.size()) {
            int g = q.front();
            q.pop();
            ne[j][g] = -1;
        }
        for(int k = 0; k < v.size(); k++) {
            lift[j][k].resize(13);
            lift[j][k][0] = ne[j][k];
        }
        for(int l = 1; l < 13; l++) {
            for(int k = 0; k < v.size(); k++) {
                if(lift[j][k][l-1] == -1) lift[j][k][l] = -1;
                else lift[j][k][l] = lift[j][lift[j][k][l-1]][l-1];
            }
        }
    }
    cout << (ll)f(0, n) << '\n';
}

Compilation message (stderr)

copypaste3.cpp: In function 'int main()':
copypaste3.cpp:81:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   81 |     for(int j = 0; j < ne.size(); j++) {
      |                    ~~^~~~~~~~~~~
copypaste3.cpp:99:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   99 |         for(int k = 0; k < v.size(); k++) {
      |                        ~~^~~~~~~~~~
copypaste3.cpp:104:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  104 |             for(int k = 0; k < v.size(); k++) {
      |                            ~~^~~~~~~~~~

• Subtask 1: 1 / 1
• Subtask 2: 0 / 5
• Subtask 3: 14 / 14
• Subtask 4: 10 / 10
• Subtask 5: 0 / 32
• Subtask 6: 0 / 38