oj.uz

Submission #785319

# Submission time Handle Problem Language Result Execution time Memory
785319 2023-07-17T08:20:59 Z 박상훈(#10022) Raspad (COI17_raspad) C++17
100 / 100
 141 ms 69024 KB 
#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

struct DSU1{
	int path[101];

	void init(int n){for (int i=1;i<=n;i++) path[i] = i;}
	int find(int s){
		if (s==path[s]) return s;
		return path[s] = find(path[s]);
	}
	bool merge(int s, int v){
		s = find(s), v = find(v);
		if (s==v) return false;
		path[v] = s;
		return true;
	}
}dsu, dsu3;

struct DSU2{
	int path[101], on[101], cur;
	
	void init(int n){
		cur = 0;
		for (int i=1;i<=n;i++){
			path[i] = i;
			cur += on[i];
			// printf(" %d", on[i]);
		}
		// printf("\n");
	}

	int find(int s){
		if (s==path[s]) return s;
		return path[s] = find(path[s]);
	}

	void merge(int s, int v){
		s = find(s), v = find(v);
		assert(s!=v);

		if (on[s] || on[v]) --cur;
		on[s] &= on[v];

		path[v] = path[s];
	}

	int count(){return cur;}
}dsu2;

struct Data{
	int p, q, t;
	Data(){}
	Data(int _p, int _q, int _t): p(_p), q(_q), t(_t) {}
};

vector<Data> Dat[100100];
char a[100100][55];
int b[100100][55], cnt[100100], to[55];
vector<int> adj[55];

ll simulate(int sx, int cntV, const vector<Data> &Dat){
	int prvT = sx;
	dsu2.init(cntV);

	ll ret = 0;

	for (const auto &[p, q, t]:Dat){
		ret += (ll)(prvT-t) * dsu2.count();
		dsu2.merge(p, q);
		prvT = t;
	}

	ret += (ll)prvT * dsu2.count();
	// printf(" fuck %d\n", dsu2.count());
	return ret;
}

ll solve(int n, int m, char a[100100][55]){
	// init here
	for (int i=1;i<=n;i++){
		Dat[i].clear();
		fill(b[i], b[i]+m+1, 0);
		cnt[i] = 0;
	}

	ll ans = 0;

	for (int i=1;i<=n;i++){
		// printf("calc %d\n", i);
		//init here
		for (int j=1;j<=cnt[i-1];j++){
			adj[j].clear();
			to[j] = 0;
		}

		// get component
		cnt[i] = 0;
		for (int j=1;j<=m;j++) if (a[i][j]=='1'){
			if (j>1 && a[i][j-1]=='1') b[i][j] = b[i][j-1];
			else b[i][j] = ++cnt[i];

			if (b[i-1][j]!=0){
				// printf(" push %d %d\n", b[i-1][j], b[i][j]);
				adj[b[i-1][j]].push_back(b[i][j]);
				to[b[i-1][j]] = b[i][j];
			}
		}

		// for (int j=1;j<=cnt[i-1];j++) printf(" %d", to[j]);
		// printf("\n");

		dsu.init(cnt[i]);

		// merge using (i-1)th row
		for (int j=1;j<=cnt[i-1];j++){
			for (int k=0;k<(int)adj[j].size()-1;k++){
				if (dsu.merge(adj[j][k], adj[j][k+1])){
					// printf("ok %d %d\n", j, k);
					Dat[i].emplace_back(adj[j][k], adj[j][k+1], i-1);
				}
			}
		}

		// reindex
		dsu3.init(cnt[i-1]);
		for (auto &[p, q, t]:Dat[i-1]){
			p = dsu3.find(p), q = dsu3.find(q);
			if (!to[p]) swap(p, q);
			dsu3.merge(p, q);
		}

		// merge using x(< i-1)th row
		for (auto &[p, q, t]:Dat[i-1]) if (to[p] && to[q]){
			if (dsu.merge(to[p], to[q])){
				Dat[i].emplace_back(to[p], to[q], t);
			}
		}

		// update ans
		fill(dsu2.on+1, dsu2.on+cnt[i]+1, 1);
		ll val1 = simulate(i, cnt[i], Dat[i]);
		ans += val1;
		// printf(" ok add %lld\n", val1);

		// calc with invalid (i-1)th row component
		fill(dsu2.on+1, dsu2.on+cnt[i-1]+1, 0);
		for (int j=1;j<=cnt[i-1];j++) if (!to[j]) dsu2.on[j] = 1;
		ll val2 = simulate(i-1, cnt[i-1], Dat[i-1]);
		ans += val2 * (n-i+1);

		// printf(" ok add %lld * %d = %lld\n", val2, n-i+1, val2 * (n-i+1));
	}

	return ans;
}


int visited[100100][55], dx[4] = {1, -1, 0, 0}, dy[4] = {0, 0, 1, -1};

void dfs(int x, int y, char a[100100][55], int s, int e, int m){
	visited[x][y] = 1;
	for (int k=0;k<4;k++){
		int nx = x + dx[k], ny = y + dy[k];

		if (nx < s || nx > e) continue;
		if (ny < 1 || ny > m) continue;
		if (a[nx][ny]!='1') continue;
		if (visited[nx][ny]) continue;
		dfs(nx, ny, a, s, e, m);
	}
}

ll count_naive(int s, int e, int m, char a[100100][55]){
	ll ans = 0;

	for (int i=s;i<=e;i++){
		fill(visited[i]+1, visited[i]+m+1, 0);
	}

	for (int i=s;i<=e;i++){
		for (int j=1;j<=m;j++) if (!visited[i][j] && a[i][j]=='1'){
			dfs(i, j, a, s, e, m);
			ans++;
		}
	}

	return ans;
}

ll naive(int n, int m, char a[100100][55]){
	ll ans = 0;

	for (int i=1;i<=n;i++){
		for (int j=i;j<=n;j++) ans += count_naive(i, j, m, a);
	}

	return ans;
}

mt19937 seed(1557);
uniform_int_distribution<int> rng(0, 2147483647);
int getrand(int l, int r){return rng(seed)%(r-l+1) + l;}

int n, m;

void gen(){
	n = getrand(1, 20);
	m = getrand(1, 20);

	for (int i=1;i<=n;i++){
		for (int j=1;j<=m;j++) a[i][j] = '0' + !!(getrand(0, 1));
		a[i][m+1] = 0;
	}
}

void stress(int tc){
	printf("-----------------------------------------\n");
	printf("Stress #%d\n", tc);

	gen();
	printf("Input:\n");
	printf("%d %d\n", n, m);
	for (int i=1;i<=n;i++){
		printf("%s\n", a[i]+1);
	}

	ll ans = naive(n, m, a);
	ll out = solve(n, m, a);

	printf("Answer: %lld\n", ans);
	printf("Output: %lld\n", out);

	assert(ans == out);
}

int main(){
	// for (int i=1;;i++) stress(i);
	int n, m;
	scanf("%d %d", &n, &m);

	for (int i=1;i<=n;i++) scanf("%s", a[i]+1);

	printf("%lld\n", solve(n, m, a));
	// printf("%lld\n", naive(n, m, a));
}

Compilation message

raspad.cpp: In function 'int main()':
raspad.cpp:242:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  242 |  scanf("%d %d", &n, &m);
      |  ~~~~~^~~~~~~~~~~~~~~~~
raspad.cpp:244:30: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  244 |  for (int i=1;i<=n;i++) scanf("%s", a[i]+1);
      |                         ~~~~~^~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 2 ms 2644 KB Output is correct
4 Correct 2 ms 2644 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 2 ms 2644 KB Output is correct
4 Correct 2 ms 2644 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 2 ms 2900 KB Output is correct
8 Correct 2 ms 2772 KB Output is correct
9 Correct 3 ms 3028 KB Output is correct
10 Correct 3 ms 3028 KB Output is correct
11 Correct 3 ms 2900 KB Output is correct
12 Correct 2 ms 3028 KB Output is correct
13 Correct 2 ms 2900 KB Output is correct

Subtask #3
35.0 / 35.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 16212 KB Output is correct
2 Correct 51 ms 30036 KB Output is correct
3 Correct 53 ms 32984 KB Output is correct
4 Correct 24 ms 27196 KB Output is correct
5 Correct 12 ms 10876 KB Output is correct
6 Correct 53 ms 31264 KB Output is correct
7 Correct 39 ms 35668 KB Output is correct
8 Correct 29 ms 25800 KB Output is correct

Subtask #4
39.0 / 39.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 2 ms 2644 KB Output is correct
4 Correct 2 ms 2644 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 2 ms 2900 KB Output is correct
8 Correct 2 ms 2772 KB Output is correct
9 Correct 3 ms 3028 KB Output is correct
10 Correct 3 ms 3028 KB Output is correct
11 Correct 3 ms 2900 KB Output is correct
12 Correct 2 ms 3028 KB Output is correct
13 Correct 2 ms 2900 KB Output is correct
14 Correct 17 ms 16212 KB Output is correct
15 Correct 51 ms 30036 KB Output is correct
16 Correct 53 ms 32984 KB Output is correct
17 Correct 24 ms 27196 KB Output is correct
18 Correct 12 ms 10876 KB Output is correct
19 Correct 53 ms 31264 KB Output is correct
20 Correct 39 ms 35668 KB Output is correct
21 Correct 29 ms 25800 KB Output is correct
22 Correct 66 ms 25828 KB Output is correct
23 Correct 136 ms 42304 KB Output is correct
24 Correct 141 ms 44048 KB Output is correct
25 Correct 75 ms 31148 KB Output is correct
26 Correct 81 ms 50276 KB Output is correct
27 Correct 70 ms 33148 KB Output is correct
28 Correct 106 ms 40128 KB Output is correct
29 Correct 100 ms 33012 KB Output is correct
30 Correct 51 ms 29908 KB Output is correct
31 Correct 105 ms 69024 KB Output is correct
32 Correct 79 ms 49804 KB Output is correct
33 Correct 73 ms 33196 KB Output is correct
34 Correct 94 ms 34796 KB Output is correct