oj.uz

Submission #62254

# Submission time Handle Problem Language Result Execution time Memory
62254 2018-07-28T00:22:13 Z kingpig9 The Kingdom of JOIOI (JOI17_joioi) C++11
100 / 100
 3104 ms 52860 KB 
#include <bits/stdc++.h>

using namespace std;
const int MAXN = 2010;

void setmin (int &a, int b) {
	if (a > b) {
		a = b;
	}
}

void setmax (int &a, int b) {
	if (a < b) {
		a = b;
	}
}

int N, M, mx = 0, mn = 1e9;
int A[MAXN][MAXN];
int msk[MAXN][MAXN];
int mnpos[2][MAXN], mxpos[2][MAXN];	//min position for each of them

void calcpos() {
	for (int i = 1; i <= N; i++) {
		mnpos[0][i] = mnpos[1][i] = M + 1;
		mxpos[0][i] = mxpos[1][i] = 0;
		for (int j = 1; j <= M; j++) {
			for (int k = 0; k < 2; k++) {
				if (msk[i][j] == (1 << k)) {
					setmin(mnpos[k][i], j);
					setmax(mxpos[k][i], j);
				}
			}
		}
	}
}

bool solve (int b) {
	//can the bit b be monotonically increasing??
	int cur = 0;

	for (int i = 1; i <= N; i++) {
		if (mxpos[b][i] > mnpos[b ^ 1][i]) {
			return false;
		}

		//so can take mxpos[b][i] <= j < mnpos[b ^ 1][i]
		if (cur >= mnpos[b ^ 1][i]) {
			return false;
		}

		setmax(cur, mxpos[b][i]);
	}

	return true;
}

bool moo (int g) {
	for (int i = 1; i <= N; i++) {
		for (int j = 1; j <= M; j++) {
			msk[i][j] = 0;
			if (A[i][j] <= mn + g) {
				msk[i][j] ^= 1;
			}
			if (A[i][j] >= mx - g) {
				msk[i][j] ^= 2;
			}

			if (msk[i][j] == 0) {
				return false;
			}
		}
	}

	calcpos();
	if (solve(0) || solve(1)) {
		return true;
	}

	//check if it can be decreasing or increasing!
	for (int i = 1; i <= N; i++) {
		reverse(msk[i] + 1, msk[i] + M + 1);
	}

	calcpos();
	if (solve(0) || solve(1)) {
		return true;
	}
	return false;
}

int main() {
	scanf("%d %d", &N, &M);

	for (int i = 1; i <= N; i++) {
		for (int j = 1; j <= M; j++) {
			scanf("%d", &A[i][j]);
			setmin(mn, A[i][j]);
			setmax(mx, A[i][j]);
		}
	}

	int lo = -1, hi = mx - mn;
	while (hi - lo > 1) {
		int mid = (lo + hi) / 2;
		if (moo(mid)) {
			hi = mid;
		} else {
			lo = mid;
		}
	}

	printf("%d\n", hi);
}

Compilation message

joioi.cpp: In function 'int main()':
joioi.cpp:93:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d", &N, &M);
  ~~~~~^~~~~~~~~~~~~~~~~
joioi.cpp:97:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d", &A[i][j]);
    ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 3 ms 576 KB Output is correct
3 Correct 3 ms 576 KB Output is correct
4 Correct 3 ms 632 KB Output is correct
5 Correct 3 ms 632 KB Output is correct
6 Correct 3 ms 632 KB Output is correct
7 Correct 3 ms 820 KB Output is correct
8 Correct 3 ms 820 KB Output is correct
9 Correct 3 ms 820 KB Output is correct
10 Correct 3 ms 820 KB Output is correct
11 Correct 3 ms 820 KB Output is correct
12 Correct 4 ms 820 KB Output is correct
13 Correct 2 ms 820 KB Output is correct
14 Correct 3 ms 820 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 3 ms 576 KB Output is correct
3 Correct 3 ms 576 KB Output is correct
4 Correct 3 ms 632 KB Output is correct
5 Correct 3 ms 632 KB Output is correct
6 Correct 3 ms 632 KB Output is correct
7 Correct 3 ms 820 KB Output is correct
8 Correct 3 ms 820 KB Output is correct
9 Correct 3 ms 820 KB Output is correct
10 Correct 3 ms 820 KB Output is correct
11 Correct 3 ms 820 KB Output is correct
12 Correct 4 ms 820 KB Output is correct
13 Correct 2 ms 820 KB Output is correct
14 Correct 3 ms 820 KB Output is correct
15 Correct 3 ms 820 KB Output is correct
16 Correct 11 ms 2604 KB Output is correct
17 Correct 19 ms 2936 KB Output is correct
18 Correct 13 ms 3316 KB Output is correct
19 Correct 26 ms 3584 KB Output is correct
20 Correct 21 ms 3584 KB Output is correct
21 Correct 22 ms 4116 KB Output is correct
22 Correct 20 ms 4376 KB Output is correct
23 Correct 32 ms 4888 KB Output is correct
24 Correct 15 ms 4892 KB Output is correct
25 Correct 33 ms 5620 KB Output is correct
26 Correct 30 ms 6008 KB Output is correct
27 Correct 25 ms 6396 KB Output is correct
28 Correct 19 ms 6784 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 3 ms 576 KB Output is correct
3 Correct 3 ms 576 KB Output is correct
4 Correct 3 ms 632 KB Output is correct
5 Correct 3 ms 632 KB Output is correct
6 Correct 3 ms 632 KB Output is correct
7 Correct 3 ms 820 KB Output is correct
8 Correct 3 ms 820 KB Output is correct
9 Correct 3 ms 820 KB Output is correct
10 Correct 3 ms 820 KB Output is correct
11 Correct 3 ms 820 KB Output is correct
12 Correct 4 ms 820 KB Output is correct
13 Correct 2 ms 820 KB Output is correct
14 Correct 3 ms 820 KB Output is correct
15 Correct 3 ms 820 KB Output is correct
16 Correct 11 ms 2604 KB Output is correct
17 Correct 19 ms 2936 KB Output is correct
18 Correct 13 ms 3316 KB Output is correct
19 Correct 26 ms 3584 KB Output is correct
20 Correct 21 ms 3584 KB Output is correct
21 Correct 22 ms 4116 KB Output is correct
22 Correct 20 ms 4376 KB Output is correct
23 Correct 32 ms 4888 KB Output is correct
24 Correct 15 ms 4892 KB Output is correct
25 Correct 33 ms 5620 KB Output is correct
26 Correct 30 ms 6008 KB Output is correct
27 Correct 25 ms 6396 KB Output is correct
28 Correct 19 ms 6784 KB Output is correct
29 Correct 1553 ms 51164 KB Output is correct
30 Correct 1757 ms 52724 KB Output is correct
31 Correct 1762 ms 52724 KB Output is correct
32 Correct 1223 ms 52760 KB Output is correct
33 Correct 794 ms 52760 KB Output is correct
34 Correct 1880 ms 52852 KB Output is correct
35 Correct 1644 ms 52852 KB Output is correct
36 Correct 1171 ms 52852 KB Output is correct
37 Correct 3104 ms 52860 KB Output is correct