Submission #530608

#	Time	Username	Problem	Language	Result	Execution time	Memory
530608		Yuisuyuno	Nafta (COI15_nafta)	C++17	100 / 100	407 ms	153688 KiB

nafta

//Nguyen Huu Hoang Minh
#include <bits/stdc++.h>
#define sz(x) int(x.size())
#define all(x) x.begin(),x.end()
#define reset(x) memset(x, 0,sizeof(x))
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define N 2005
#define remain(x) if (x > MOD) x -= MOD
#define ii pair<int, int>
#define iiii pair< ii , ii >
#define viiii vector< iiii >
#define vi vector<int>
#define vii vector< ii >
#define bit(x, i) (((x) >> (i)) & 1)
#define Task "test"
#define int long long

using namespace std;

typedef long double ld;
const int inf = 1e10;
const int minf = -1e10;

int m, n;
char a[N][N];
int vst[N][N];

void readfile()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    if (fopen(Task".inp","r"))
    {
        freopen(Task".inp","r",stdin);
        //freopen(Task".out","w",stdout);
    }
    cin >> n >> m;
    for(int i=1; i<=n; i++){
        for(int j=1; j<=m; j++){
            cin >> a[i][j];
        }
    }
}

vector<ii> vec[N];
int dx[4] = {1,-1,0,0};
int dy[4] = {0,0,1,-1};

bool ok(int x, int y){
    return 1 <= x && x <= n && 1 <= y && y <= m;
}

void dfs(int u, int v, int &l, int &r, int &dep){
    for(int i=0; i<4; i++){
        int x = u + dx[i];
        int y = v + dy[i];
        if (!ok(x,y) || a[x][y]=='.' || vst[x][y]) continue;
        vst[x][y] = 1;
        l = min(l,y);
        r = max(r,y);
        dep += a[x][y]-'0';
        dfs(x,y,l,r,dep);
    }
}

int g[N][N];
vector<vector<int>> f(2001,vector<int>(2001,0));

void solve(int cur, int l, int r, int otpl, int otpr){
    if (l > r) return;
    int mid = (l+r)>>1;
    ii Best = {minf,-1};
    for(int k=otpl; k<=min(mid,otpr); k++){
        Best = max(Best,{f[cur-1][k-1] + g[k][mid],k});
    }
    f[cur][mid] = Best.fi;
    solve(cur,l,mid-1,otpl,Best.se);
    solve(cur,mid+1,r,Best.se,otpr);
}

void proc(){
    for(int i=1; i<=n; i++){
        for(int j=1; j<=m; j++){
            if (a[i][j]!='.' && !vst[i][j]){
                vst[i][j] = 1;
                int l = j, r = j, dep = a[i][j]-'0';
                dfs(i,j,l,r,dep);
                vec[l].pb(ii(r,dep));
            }
        }
    }
    vector<int> cnt(m+2,0);
    for(int i=m; i>=1; i--){
        for(auto x : vec[i]){
            for(int j=i; j<=x.fi; j++) cnt[j]+=x.se;
        }
        for(int j=i; j<=m; j++) g[i][j] = cnt[j];
    }
    for(int i=1; i<=m; i++){
        solve(i,1,m,1,m);
        int ans = 0;
        for(int j=1; j<=m; j++) ans = max(ans,f[i][j]);
        cout << ans << '\n';
    }
}

signed main()
{
    readfile();
    proc();
    return 0;
}

Compilation message (stderr)

nafta.cpp: In function 'void readfile()':
nafta.cpp:37:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |         freopen(Task".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

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