Submission #576669

#	Time	Username	Problem	Language	Result	Execution time	Memory
576669		MadokaMagicaFan	Carnival Tickets (IOI20_tickets)	C++14	16 / 100	3073 ms	134912 KiB

tickets

#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using vi = vector<int>;
using vll = vector<ll>;
using pi = pair<int,int>;

const ll inf = 1e10;

#define all(v)          v.begin(),v.end()
#define sort(v)         sort(all(v))
#define endl            '\n'
#define forn(i,n)       for(int i = 0; i < n; ++i)
#define forbe(i,b,e)    for(int i = b; i < e; ++i)
#define forr(i,n)       for(int i = n-1; i >= 0; --i)
#define sz(v)           ((int)v.size())
#define pb              push_back
#define f               first
#define s               second

//#define ONTST

const int N = 1505;
const int M = 1505;

void allocate_tickets(vector<vi>s);


using pl = pair<ll,int>;

ll subtaskidk(int k, vector<vi> &x) {
    int n = sz(x);
    int m = sz(x[0]);
    vector<vi> s(n);
    vector<pair<ll,int>> vals;
    forn(i,n) s[i].assign(m,-1);
    vector<vector<pair<ll,int>>> sval(n);

    int topp[N];
    int botp[N];

    forn(i,n) {
        forn(j,m) {
            sval[i].pb({x[i][j], j});
        }
        sort(sval[i]);
    }

    bitset<N*M> c;
    bitset<N*M> z;

    forn(i,n) {
        if (i < (n>>1)) {
            topp[i] = m-1;
            botp[i] = k;
        } else {
            topp[i] = m-1-k;
            botp[i] = 0;
        }
    }

//    priority_queue<pl> q1;
//    priority_queue<pl, vector<pl>, greater<pl>> q2;
//    
//    forn(i,n) {
//        if (botp[i])    q1.push({sval[i][ botp[i]-1 ].f + sval[i][ topp[i] ].f, i});
//        else            q1.push({-inf,i});
//
//        if (topp[i]<m-1)    q2.push({sval[i][ botp[i] ].f + sval[i][ topp[i]+1 ].f, i});
//        else                q2.push({inf,i});
//    }
//    while (sz(q1)) {
//        auto u1 = q1.top();
//        auto u2 = q2.top();
//
//        if (u1.f <= u2.f)
//            break;
//        
//        --botp[u1.s];
//        --topp[u1.s];
//        ++botp[u2.s];
//        ++topp[u2.s];
//        q1.pop();
//        q2.pop();
//    }
    ll minval, maxval;
    int mnp, mxp;
    while (1) {
        mnp = mxp = -1;
        minval = inf;
        maxval = -inf;
        forn(i, n) {
            if (botp[i]) {
                if (maxval < sval[i][ botp[i]-1 ].f + sval[i][ topp[i] ].f) {
                    maxval = sval[i][ botp[i]-1 ].f + sval[i][ topp[i] ].f;
                    mxp = i;
                }
            }
            if (topp[i]<m-1) {
                if (minval > sval[i][ botp[i] ].f + sval[i][ topp[i]+1 ].f) {
                    minval = sval[i][ botp[i] ].f + sval[i][ topp[i]+1 ].f;
                    mnp = i;
                }
            }
        }

        if (minval >= maxval)
            break;
        --botp[mxp];
        --topp[mxp];
        ++topp[mnp];
        ++botp[mnp];
    }

    forn(i,n) {
        assert(botp[i]>=0);
        assert(topp[i]>=0);
        assert(botp[i]<=m-1);
        assert(topp[i]<=m-1);
        assert(m-1 + botp[i] - topp[i] == k);
    }

    ll ans = 0;
    forn(i ,n) {
        for(int j = m-1; j > topp[i]; --j) c[ i*m + sval[i][j].s ] = 1;
        for(int j = m-1; j > topp[i]; --j) ans += sval[i][j].f;
        for(int j = 0; j < botp[i]; ++j)  z[ i*m + sval[i][j].s ] = 1;
        for(int j = 0; j < botp[i]; ++j)  ans -= sval[i][j].f;
    }

    forn(i,n) {
        forn(j,m) {
            if (c[ i*m + j ]) {
                vals.pb({x[i][j] * 2 + 1,i * m + j});
            } else {
                vals.pb({x[i][j] * 2,i * m + j});
            }
        }
    }
    sort(vals);

    forn(i,n) {
        topp[i] = m-1;
        botp[i] = 0;
    }

    bitset<N> up;
    bitset<N> us;
    int cnt;
    int ucnt;
    int u = 0;
    int str = 0;
    int ind;
    queue<int> b[N];
    queue<int> t[N];
    #ifdef ONTST
    forn(j,m) {
        forn(i,n) {
            cout << c[i*m+j] << ' ';
        }
        cout << endl;
    }

    forn(j,m) {
        forn(i,n) {
            cout << z[i*m+j] << ' ';
        }
        cout << endl;
    }
    #endif
    int bcnt = 0;
    int rcnt = 0;
    while (u < k) {
        cnt = 0;
        ucnt = 0;
        rcnt = 0;
        forn(i,n) {
            up[i] = 0;
            us[i] = 0;
            if (sz(t[i])) {
                up[i] = 1;
                us[i] = 1;
                ++cnt;
                ++ucnt;
            } else if (sz(b[i])) {
                us[i] = 1;
                ++cnt;
            }
        }
        while (cnt < n || ucnt < (n>>1)) {
//            assert(str < sz(vals));
            ind = vals[str].s;
            ++str;
//            printf("std(%d), i(%d), j(%d), v(%d), c(%d), z(%d)\n", str, ind/m, ind%m, vals[str].f, (int)c[ind], (int)z[ind]);
            if (c[ ind ]) {
                t[ind/m].push(ind);
//                assert(bcnt == ((n*k)>>1));
                if (!up[ind/m])
                    ++ucnt;
                up[ind/m] = 1;
                if (!us[ind/m]) {
                    us[ind/m] = 1;
                    ++cnt;
                }
            }

            if (z[ ind ]) {
                ++bcnt;
                b[ind/m].push(ind);
                if (!us[ind/m]) {
                    us[ind/m] = 1;
                    ++cnt;
                }
            }
        }
        forn(i,n) {
//            assert(rcnt <= (n>>1));
            if (up[i] && (sz(b[i]) == 0)) {
//                printf("Day %d: i(%d), j(%d), top\n", u, i, t[i].front()%m);
                s[i][t[i].front()%m] = u;
                t[i].pop();
                ++rcnt;
                us[i] = 0;
            }
        }
        
        forn(i,n) {
            if (!us[i]) continue;
            if (up[i] && rcnt < (n>>1)) {
//                printf("Day %d: i(%d), j(%d), top\n", u, i, t[i].front()%m);
                s[i][t[i].front()%m] = u;
                t[i].pop();
                ++rcnt;
            } else {
//                printf("Day %d: i(%d), j(%d), bot\n", u, i, b[i].front()%m);
                s[i][b[i].front()%m] = u;
                b[i].pop();
            }
        }

//        assert(rcnt == (n>>1));
        ++u;
    }

    allocate_tickets(s);

    return ans;
}


ll find_maximum(int k, vector<vi>x) {
    int n = sz(x);
    int m = sz(x[0]);
//    if (m == 1) return subtask1(k,x);
//    if (k == 1) return subtask2(k,x);
//    if (m == k) return subtask4(k,x);

    return subtaskidk(k,x);
}

#ifdef ONPC
void allocate_tickets(vector<vi>s) {
    forn(i, sz(s)) {
        forn(j, sz(s[0])) {
            cout << s[i][j] << ' ';
        }
        cout << endl;
    }
}

void solve() {
    int n, m, k;
    cin >> n >> m >> k;
    vector<vi> x(n);
    forn(i,n) {
        x[i].assign(m,0);
    }

    forn(j,m) {
        forn(i,n) {
            cin >> x[i][j];
        }
    }

    cout << find_maximum(k, x) << endl;
}

int main(int argc, char **argv) {
    freopen("input", "r", stdin);
//    ios_base::sync_with_stdio(0);cin.tie(0);
    solve();
}
#endif

Compilation message (stderr)

tickets.cpp: In function 'll find_maximum(int, std::vector<std::vector<int> >)':
tickets.cpp:254:9: warning: unused variable 'n' [-Wunused-variable]
  254 |     int n = sz(x);
      |         ^
tickets.cpp:255:9: warning: unused variable 'm' [-Wunused-variable]
  255 |     int m = sz(x[0]);
      |         ^

• Subtask 1: 0 / 11
• Subtask 2: 16 / 16
• Subtask 3: 0 / 14
• Subtask 4: 0 / 14
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23
• Subtask 7: 0 / 10