oj.uz

Submission #792701

# Submission time Handle Problem Language Result Execution time Memory
792701 2023-07-25T08:10:38 Z 박상훈(#10052) Line Town (CCO23_day1problem3) C++17
7 / 25
 494 ms 19856 KB 
#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

constexpr ll INF = 4e18;

struct Seg{
	int tree[2002000];
	int sz;

	void init(int n){
		sz = n;
		fill(tree, tree+sz*2, 0);
	}

	void update(int p, ll x){
		p += sz;
		tree[p] = x;
		for (p>>=1;p;p>>=1) tree[p] = tree[p<<1] + tree[p<<1|1];
	}

	int query(int l, int r){
		++r;
		int ret = 0;
		for (l+=sz, r+=sz;l<r;l>>=1, r>>=1){
			if (l&1) ret += tree[l++];
			if (r&1) ret += tree[--r];
		}

		return ret;
	}
}tree;

int a[500500], I[500500];
ll dp[2][500500];

int cnt2[2], col_b[500500], col_f[500500], col[500500];

int f(int s, int e, int val){
	if ((e-s)%2 == 0) return val;
	return -val;
}

int main(){
	int n;
	scanf("%d", &n);
	for (int i=1;i<=n;i++) scanf("%d", a+i);

	for (int i=1;i<=n;i++){
		if (f(i, 0, a[i]) == -abs(a[i])) col[i] = 0;
		else col[i] = 1;
	}

	for (int i=1;i<=n;i++) I[i] = i;
	sort(I+1, I+n+1, [&](int i, int j){return abs(a[i]) < abs(a[j]);});
	tree.init(n+1);

	for (int i=1,r;i<=n;i=r+1){
		r = i;
		while(r+1<=n && abs(a[I[i]]) == abs(a[I[r+1]])) r++;

		for (int t=i;t<=r;t++) tree.update(I[t], 1);

		for (int z=0;z<2;z++){
			int len = r;
			int cnt = r-i+1;
			dp[z][len] = INF;

			if (len==1) dp[z][len] = 0;

			for (int s=0;s<2;s++){

				// init here
				vector<int> V[2];
				cnt2[0] = cnt2[1] = 0;

				for (int t=i;t<=r;t++){
					int idx = I[t];

					V[col[idx]].push_back(tree.query(1, idx));
				}


				col_f[0] = z^1;
				for (int i=1;i<=cnt;i++){
					col_f[i] = col_f[i-1] ^ 1;
					if (i<=s) cnt2[col_f[i]]++; 
				}

				col_b[len] = ((z+len-1)&1) ^ 1;
				if (len >= len-(cnt-s)+1) cnt2[col_b[len]]++;
				for (int i=len-1;i>=len-(cnt-s)+1;i--){
					col_b[i] = col_b[i+1] ^ 1;
					cnt2[col_b[i]]++;
				}

				// printf("\ni = %d, z = %d, s = %d -> cnt = (%d, %d) / sz = (%d, %d)\n", i, z, s, cnt2[0], cnt2[1], (int)V[0].size(), (int)V[1].size());

				if (cnt2[0]!=(int)V[0].size() || cnt2[1]!=(int)V[1].size()) continue;

				int cp[2] = {col_f[s+1], col_f[s+2]};
				int cq[2] = {col_b[len - (cnt-s) + 1], col_b[len - (cnt-s) + 2]};

				int pp[2] = {0, 0}, pq[2] = {0, 0};
				if (s==1) {
					pp[1] = 1;
					if (cq[0]==z) pq[0]++;
					else pq[1]++;
				}

				ll cst = 0;
				cnt2[0] = cnt2[1] = 0;
				for (int i=1;i<=s;i++){
					cst += abs(V[col_f[i]][cnt2[col_f[i]]] - i);
					cnt2[col_f[i]]++;
				} 

				for (int i=len-(cnt-s)+1;i<=len;i++){
					cst += abs(V[col_b[i]][cnt2[col_b[i]]] - i);
					cnt2[col_b[i]]++;
				}

				int nz = z ^ s;

				// printf("i = %d, z = %d, s = %d -> cst = %lld\n", i, z, s, cst);


				for (int k=s;k<=cnt;k+=2){
					dp[z][len] = min(dp[z][len], dp[nz][i-1] + cst);
					if (k+2 > cnt) break;

					cst -= abs(V[cq[0]][pq[0]] - (len - (cnt-k) + 1));
					cst -= abs(V[cq[1]][pq[1]] - (len - (cnt-k) + 2));

					pq[0]++, pq[1]++;

					cst += abs(V[cp[0]][pp[0]] - (k+1));
					cst += abs(V[cp[1]][pp[1]] - (k+2));

					pp[0]++, pp[1]++;
				}
			}

			// printf("%d %d -> %lld\n", i, z, dp[z][i]);
		}


		// assert(i==r);

		// // abs distinct
		// int pos = I[i];
		// for (int z=0;z<2;z++){
		// 	dp[z][i] = INF;

		// 	if (f(pos, z, a[pos]) == -abs(a[pos])) dp[z][i] = min(dp[z][i], dp[z^1][i-1] + tree.query(1, pos-1));
		// 	if (f(pos, z+i-1, a[pos]) == abs(a[pos])) dp[z][i] = min(dp[z][i], dp[z][i-1] + tree.query(pos+1, n));

		// 	if (i==1) dp[z][i] = 0;

		// 	// printf("%d %d -> %lld\n", z, i, dp[z][i]);
		// }

		// tree.update(pos, 1);
	}

	if (dp[1][n]==INF) printf("-1\n");
	else printf("%lld\n", dp[1][n]);
}

Compilation message

Main.cpp: In function 'int main()':
Main.cpp:47:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
Main.cpp:48:30: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |  for (int i=1;i<=n;i++) scanf("%d", a+i);
      |                         ~~~~~^~~~~~~~~~~

Subtask #1
0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 1 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #2
0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 1 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #3
0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 1 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #4
0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 1 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #5
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 2 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 2 ms 432 KB Output is correct
13 Correct 2 ms 432 KB Output is correct

Subtask #6
3.0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 2 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 2 ms 432 KB Output is correct
13 Correct 2 ms 432 KB Output is correct
14 Correct 279 ms 19808 KB Output is correct
15 Correct 494 ms 19768 KB Output is correct
16 Correct 447 ms 19800 KB Output is correct
17 Correct 396 ms 19848 KB Output is correct
18 Correct 396 ms 19856 KB Output is correct
19 Correct 479 ms 19836 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
21 Correct 0 ms 340 KB Output is correct
22 Correct 340 ms 19852 KB Output is correct
23 Correct 339 ms 19840 KB Output is correct
24 Correct 282 ms 19832 KB Output is correct

Subtask #7
0 / 2.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 1 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #8
0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 1 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -