#include <bits/stdc++.h>
using namespace std;
#define int long long
typedef pair<int, int> pii;
const int MXN = 2005;
int n, m, a[MXN][MXN], b[MXN][MXN];
int big = 0, small = LLONG_MAX;
int l, r;
set<int> S;
bool CHECK() {
vector<int> v;
int f = 0;
for (int i = 0; i < n; i++) {
v.clear();
for (int j = 0; j < m; j++) {
if (b[i][j] != 0) v.push_back(b[i][j]);
}
int C = 0;
for (int i = 1; i < v.size(); i++) {
if (v[i] != v[i - 1]) {
if (++C == 2) return false;
}
}
if (C == 0) continue;
if (f == 0) f = v[0];
else if (f != v[0]) return false;
}
f = 0;
for (int i = 0; i < m; i++) {
v.clear();
for (int j = 0; j < n; j++) {
if (b[j][i] != 0) v.push_back(b[j][i]);
}
int C = 0;
for (int i = 1; i < v.size(); i++) {
if (v[i] != v[i - 1]) {
if (++C == 2) return false;
}
}
if (C == 0) continue;
if (f == 0) f = v[0];
else if (f != v[0]) return false;
}
return true;
}
bool check(int x) {
if (x * 2 >= big) { // cross
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
if (a[i][j] < big - x) b[i][j] = 1;
else if (x < a[i][j]) b[i][j] = 2;
else b[i][j] = 0;
}
}
} else { // not cross
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
if (a[i][j] <= x) b[i][j] = 1;
else if (r - x <= a[i][j]) b[i][j] = 2;
else return false;
}
}
}
return CHECK();
}
int32_t main() {
cin.tie(0) -> sync_with_stdio(false);
cin >> n >> m;
for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) {
cin >> a[i][j];
S.insert(a[i][j]);
big = max(big, a[i][j]);
small = min(small, a[i][j]);
}
for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) {
a[i][j] -= small;
}
big -= small;
int l = -1, r = big;
while (l + 1 < r) {
int mid = (l + r) >> 1;
(check(mid) ? r : l) = mid;
}
cout << r << endl;
return 0;
}
Compilation message
joioi.cpp: In function 'bool CHECK()':
joioi.cpp:22:27: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
22 | for (int i = 1; i < v.size(); i++) {
| ~~^~~~~~~~~~
joioi.cpp:38:27: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
38 | for (int i = 1; i < v.size(); i++) {
| ~~^~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |