oj.uz

Submission #443706

# Submission time Handle Problem Language Result Execution time Memory
443706 2021-07-11T14:54:22 Z BeanZ Tracks in the Snow (BOI13_tracks) C++14
100 / 100
 1036 ms 143144 KB 
// I_Love_LPL 1y0m2d
#include <bits/stdc++.h>
using namespace std;
#define ll int
#define endl '\n'
const int N = 4005;
long long mod = 1000007;
const int lim = 4e5 + 5;
const int lg = 20;
const int base = 311;
const long double eps = 1e-6;
ll nx[4] = {0, 0, 1, -1};
ll ny[4] = {1, -1, 0, 0};
char a[N][N];
ll dp[N][N];
struct viet{
    ll x, y, v;
};
ll n, m;
bool check(ll x, ll y){
    if (x < 1 || x > n || y < 1 || y > m || a[x][y] == '.') return false;
    else return true;
}
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    if (fopen("tests.inp", "r")){
        freopen("test.inp", "r", stdin);
        freopen("test.out", "w", stdout);
    }
    cin >> n >> m;
    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            cin >> a[i][j];
            dp[i][j] = 1e9;
        }
    }
    deque<viet> q;
    q.push_back({1, 1, 1});
    dp[1][1] = 1;
    ll ans = 1;
    while (q.size()){
        viet x = q.front();
        ans = max(ans, x.v);
        q.pop_front();
        for (int i = 0; i < 4; i++){
            ll nwx = x.x + nx[i];
            ll nwy = x.y + ny[i];
            if (!check(nwx, nwy)) continue;
            ll cost = x.v + (a[nwx][nwy] != a[x.x][x.y]);
            if (dp[nwx][nwy] > cost){
                dp[nwx][nwy] = cost;
                if (cost == x.v) q.push_front({nwx, nwy, cost});
                else q.push_back({nwx, nwy, cost});
            }
        }
    }
    cout << ans;
}
/*
Ans:

Out:
*/

Compilation message

tracks.cpp: In function 'int main()':
tracks.cpp:28:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   28 |         freopen("test.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:29:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   29 |         freopen("test.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 5196 KB Output is correct
2 Correct 1 ms 460 KB Output is correct
3 Correct 1 ms 716 KB Output is correct
4 Correct 10 ms 5048 KB Output is correct
5 Correct 4 ms 2892 KB Output is correct
6 Correct 1 ms 460 KB Output is correct
7 Correct 1 ms 716 KB Output is correct
8 Correct 1 ms 716 KB Output is correct
9 Correct 1 ms 1100 KB Output is correct
10 Correct 4 ms 2508 KB Output is correct
11 Correct 3 ms 2124 KB Output is correct
12 Correct 7 ms 3020 KB Output is correct
13 Correct 4 ms 2892 KB Output is correct
14 Correct 4 ms 2892 KB Output is correct
15 Correct 15 ms 5196 KB Output is correct
16 Correct 17 ms 5196 KB Output is correct
17 Correct 12 ms 5060 KB Output is correct
18 Correct 10 ms 5120 KB Output is correct

Subtask #2
70.0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 30796 KB Output is correct
2 Correct 73 ms 16252 KB Output is correct
3 Correct 447 ms 78692 KB Output is correct
4 Correct 136 ms 29932 KB Output is correct
5 Correct 305 ms 59088 KB Output is correct
6 Correct 1036 ms 98232 KB Output is correct
7 Correct 17 ms 32204 KB Output is correct
8 Correct 17 ms 30776 KB Output is correct
9 Correct 3 ms 588 KB Output is correct
10 Correct 1 ms 460 KB Output is correct
11 Correct 17 ms 31576 KB Output is correct
12 Correct 2 ms 1484 KB Output is correct
13 Correct 66 ms 16288 KB Output is correct
14 Correct 38 ms 11084 KB Output is correct
15 Correct 37 ms 12148 KB Output is correct
16 Correct 29 ms 5896 KB Output is correct
17 Correct 178 ms 32132 KB Output is correct
18 Correct 149 ms 32016 KB Output is correct
19 Correct 124 ms 29900 KB Output is correct
20 Correct 101 ms 27680 KB Output is correct
21 Correct 262 ms 61068 KB Output is correct
22 Correct 299 ms 59180 KB Output is correct
23 Correct 331 ms 49352 KB Output is correct
24 Correct 300 ms 60504 KB Output is correct
25 Correct 671 ms 78692 KB Output is correct
26 Correct 1016 ms 143144 KB Output is correct
27 Correct 940 ms 105580 KB Output is correct
28 Correct 945 ms 98292 KB Output is correct
29 Correct 967 ms 95024 KB Output is correct
30 Correct 978 ms 102696 KB Output is correct
31 Correct 709 ms 63612 KB Output is correct
32 Correct 985 ms 103656 KB Output is correct