Submission #728337

#	Time	Username	Problem	Language	Result	Execution time	Memory
728337		bLIC	Nafta (COI15_nafta)	C++17	11 / 100	1074 ms	43664 KiB

nafta

/**
 *  Author: Anil Byar
**/

#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>

// using namespace __gnu_pbds;
using namespace std;

// template<class T>
// using ordered_set = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;



#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)(x).size()
#define uniq(v) v.erase(unique(all(v)), v.end())
#define ft first
#define sd second
#define pb push_back

// Source: https://codeforces.com/blog/entry/68809
// { start
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...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif
// } end


typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii> vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef vector<vi> vvi;
typedef vector<vii> vvii;
typedef vector<vl> vvl;

#define dbg if(0)

const ll MOD = 1e9+7;
const ll MOD9 = 998244353;
const ll INFLL = 1e18+5;
const int INF = 1e9;

void printbit(int x, int len) {string s="\n";while(len--){s=((x%2)?'1':'0')+s;x/=2;} cout<<s;}
ll power(ll x, ll y, ll mod){if (y==0) return 1;ll ret = power(x, y/2, mod);ret *= ret;ret%=mod;if (y&1) ret *= x;return ret%mod;}
ll modinv(ll x, ll mod = MOD) {return power(x, mod-2, mod);}

template<class T>
istream& operator>>(istream&in, vector<T>&v){
    for (T& x:v) in>>x;
    return in;
}
template<class T>
ostream& operator<<(ostream&out, vector<T>&v){
    for (T& x:v) out<<x<<' ';
    cout<<'\n';
    return out;
}
// use ?: with brackets (?:)
// check for overflow
// think about dp
// Read the statement carefully

const int N = 2005;


int ver[] = {1, 0, 0, -1};
int hor[] = {0, 1, -1, 0};

void solve(){
    int n, m;cin>>n>>m;
    string s[N];
    char grid[N][N];
    memset(grid, 0, sizeof(grid));
    for (int i = 1;i<=n;i++) {
        cin>>s[i];
        for (int j = 0;j<m;j++) grid[i][j+1] = s[i][j];
    }

    bool vis[N][N];
    memset(vis, 0, sizeof(vis));
    int l, r;
    int profit;
    function<void(int, int)> dfs = [&](int row, int col){
        if (row<1 || row>n || col<1 || col>m || vis[row][col] || grid[row][col]=='.') return;
        vis[row][col] = true;
        l = min(l, col);
        r = max(r, col);
        profit += grid[row][col] - '0';
        for (int i = 0;i<4;i++){
            dfs(row+ver[i], col+hor[i]);
        }
    };
    ll totprofit[N][N];
    memset(totprofit, 0, sizeof(totprofit));

    for (int i = 1;i<=n;i++){
        for (int j = 1;j<=m;j++){
            if (grid[i][j]!='.' && !vis[i][j]){
                l = r = j;
                profit = 0;
                dfs(i, j);
                totprofit[0][l] += profit;
                totprofit[l][l] -= profit;
                totprofit[0][r+1] -= profit;
                totprofit[l][r+1] += profit;
                debug(i, j, profit);
            }
        }
    }
    for (int i = 1;i<=max(m, n);i++) totprofit[0][i] += totprofit[0][i-1], totprofit[i][0] += totprofit[i-1][0];
    for (int i = 1;i<=m;i++){
        for (int j = 1;j<=m;j++){
            totprofit[i][j] += totprofit[i-1][j] + totprofit[i][j-1] - totprofit[i-1][j-1];
            debug(i, j, totprofit[i][j]);
        }
    }
    vector<ll> olddp(m+1), newdp(m+1);
    for (int i = 1;i<=m;i++) olddp[i] = totprofit[0][i];

    debug(olddp);

    function<void(int, int, int, int)> dac = [&](int l, int r, int lx, int rx){
        if (l>r) return;
        int mid = (l+r)/2;
        pll best = {olddp[mid], 1};
        debug(l, r, lx, rx);
        for (int i = lx;i<min(mid, rx+1);i++){
            if (olddp[i]<0) continue;
            best = max(best, {olddp[i] + totprofit[i][mid], i});
            debug(mid, best, i);
        }
        newdp[mid] = best.first;
        int ind = best.second;
        dac(l, mid-1, lx, ind);
        dac(mid+1, r, ind, rx);
    };
    cout<<*max_element(all(olddp))<<'\n';
    for (int i = 1;i<m;i++){
        dac(1, m, 1, m);
        olddp = newdp;
        debug(i, olddp);
        cout<<*max_element(all(olddp))<<'\n';
    }
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);


#define ONLINE_JUDGE
#ifndef ONLINE_JUDGE
    freopen("input.in", "r", stdin);
    freopen("output.out", "w", stdout);
    freopen("debug.dbg", "w", stderr);
    int tt = clock();
#endif

    int t=1, i = 1;
    // cin>>t;
    while(t--){
        // cout<<"Case #"<<i++<<": ";
        solve();
        cout<<'\n';
    }
#ifndef ONLINE_JUDGE
    cerr << "TIME = " << (float)(clock() - tt)/CLOCKS_PER_SEC << endl;
    tt = clock();
#endif
}

Compilation message (stderr)

nafta.cpp: In function 'int main()':
nafta.cpp:191:14: warning: unused variable 'i' [-Wunused-variable]
  191 |     int t=1, i = 1;
      |              ^

• Subtask 1: 11 / 11
• Subtask 2: 0 / 23
• Subtask 3: 0 / 66