Submission #57987

#	Time	Username	Problem	Language	Result	Execution time	Memory
57987		Benq	Bob (COCI14_bob)	C++14	120 / 120	205 ms	64432 KiB

bob

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

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)

#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 100001;

ll ans = 0;

template<int SZ> struct DSU {
    int par[SZ], sz[SZ];
    DSU() {
        F0R(i,SZ) par[i] = -1, sz[i] = 1;
    }
    
    int get(int x) { // path compression
        if (par[x] != x) par[x] = get(par[x]);
        return par[x];
    }
    
    bool unite(int x, int y, int z) { // union-by-rank
        x = get(x), y = get(y);
        if (sz[x] < sz[y]) swap(x,y);
        ans += z*sz[x]*sz[y];
        sz[x] += sz[y], par[y] = x;
        return 1;
    }
};
 
int n,m,cur[1000];
int g[1000][1000];
vi nex[1001];
 
void solve(int x) {
    F0R(i,m+1) nex[i].clear();
    F0R(i,n) nex[cur[i]-x].pb(i);
    
    DSU<1000> D = DSU<1000>();
    F0Rd(i,m+1) for (int a: nex[i]) {
        // cout << a << "\n";
        D.par[a] = a; ans += i;
        if (a > 0 && D.par[a-1] != -1 && g[a][x] == g[a-1][x]) D.unite(a,a-1,i);
        if (a < n-1 && D.par[a+1] != -1 && g[a][x] == g[a+1][x]) D.unite(a,a+1,i);
    }
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n >> m;
    F0R(i,n) F0R(j,m) cin >> g[i][j];
    
    F0R(i,n) cur[i] = m;
    F0Rd(j,m) {
        if (j != m-1) F0R(i,n) if (g[i][j] != g[i][j+1]) cur[i] = j+1;
        solve(j);
    }
    cout << ans;
}

/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( ) 
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/

• Subtask 1: 12 / 12
• Subtask 2: 12 / 12
• Subtask 3: 12 / 12
• Subtask 4: 12 / 12
• Subtask 5: 12 / 12
• Subtask 6: 12 / 12
• Subtask 7: 12 / 12
• Subtask 8: 12 / 12
• Subtask 9: 12 / 12
• Subtask 10: 12 / 12