Task: | Thin Ice |
Sender: | John Hedin |
Submission time: | 2024-03-20 21:47:20 +0200 |
Language: | C++ (C++17) |
Status: | READY |
Result: | 54 |
group | verdict | score |
---|---|---|
#1 | ACCEPTED | 17 |
#2 | ACCEPTED | 12 |
#3 | ACCEPTED | 11 |
#4 | WRONG ANSWER | 0 |
#5 | ACCEPTED | 14 |
#6 | WRONG ANSWER | 0 |
test | verdict | time | group | |
---|---|---|---|---|
#1 | ACCEPTED | 0.00 s | 1, 5, 6 | details |
#2 | ACCEPTED | 0.00 s | 1, 5, 6 | details |
#3 | ACCEPTED | 0.00 s | 1, 5, 6 | details |
#4 | ACCEPTED | 0.00 s | 1, 5, 6 | details |
#5 | ACCEPTED | 0.00 s | 1, 5, 6 | details |
#6 | ACCEPTED | 0.00 s | 1, 5, 6 | details |
#7 | ACCEPTED | 0.00 s | 1, 5, 6 | details |
#8 | ACCEPTED | 0.00 s | 1, 5, 6 | details |
#9 | ACCEPTED | 0.00 s | 1, 2, 5, 6 | details |
#10 | ACCEPTED | 0.15 s | 2, 6 | details |
#11 | ACCEPTED | 0.14 s | 2, 6 | details |
#12 | ACCEPTED | 0.15 s | 2, 6 | details |
#13 | ACCEPTED | 0.14 s | 2, 6 | details |
#14 | ACCEPTED | 0.14 s | 2, 6 | details |
#15 | ACCEPTED | 0.14 s | 2, 6 | details |
#16 | ACCEPTED | 0.15 s | 2, 6 | details |
#17 | ACCEPTED | 0.15 s | 2, 6 | details |
#18 | ACCEPTED | 0.15 s | 2, 6 | details |
#19 | ACCEPTED | 0.15 s | 2, 6 | details |
#20 | ACCEPTED | 0.16 s | 2, 6 | details |
#21 | ACCEPTED | 0.13 s | 2, 6 | details |
#22 | ACCEPTED | 0.00 s | 3, 4, 5, 6 | details |
#23 | ACCEPTED | 0.00 s | 3, 4, 5, 6 | details |
#24 | ACCEPTED | 0.01 s | 3, 4, 5, 6 | details |
#25 | ACCEPTED | 0.01 s | 3, 4, 5, 6 | details |
#26 | ACCEPTED | 0.00 s | 3, 4, 5, 6 | details |
#27 | ACCEPTED | 0.00 s | 3, 4, 5, 6 | details |
#28 | WRONG ANSWER | 0.69 s | 4, 6 | details |
#29 | ACCEPTED | 0.25 s | 4, 6 | details |
#30 | ACCEPTED | 0.24 s | 4, 6 | details |
#31 | ACCEPTED | 0.46 s | 4, 6 | details |
#32 | ACCEPTED | 0.32 s | 4, 6 | details |
#33 | ACCEPTED | 0.21 s | 4, 6 | details |
#34 | WRONG ANSWER | 0.67 s | 4, 6 | details |
#35 | ACCEPTED | 0.01 s | 5, 6 | details |
#36 | ACCEPTED | 0.01 s | 5, 6 | details |
#37 | ACCEPTED | 0.01 s | 5, 6 | details |
#38 | ACCEPTED | 0.01 s | 5, 6 | details |
#39 | ACCEPTED | 0.01 s | 5, 6 | details |
#40 | ACCEPTED | 0.01 s | 5, 6 | details |
#41 | ACCEPTED | 0.01 s | 5, 6 | details |
#42 | ACCEPTED | 0.29 s | 6 | details |
#43 | ACCEPTED | 0.29 s | 6 | details |
#44 | ACCEPTED | 0.34 s | 6 | details |
#45 | ACCEPTED | 0.37 s | 6 | details |
#46 | ACCEPTED | 0.28 s | 6 | details |
#47 | ACCEPTED | 0.35 s | 6 | details |
#48 | ACCEPTED | 0.29 s | 6 | details |
Code
#include <iostream>#include <vector>#include <set>using namespace std;bool debug = false;typedef long long ll;typedef vector<ll> vll;typedef vector<vll> vvll;typedef pair<ll,ll> pll;typedef set<pll> sp;typedef vector<sp> vsp;#define rep(a,b,c) for(ll a = b; a < c; a++)#define rrep(a,b,c) for(ll a = c-1; a >= b; a--)#define itr_rep(a,b,_type) for(_type::iterator a = b.begin(); a != b.end(); a++)#define pb push_back#define mp make_pair#define sz size#define all(a) a.begin(),a.end()ll uf_parent(ll a);ll uf_merge(ll a, ll b);bool try_D();ll ans;ll n;ll m;vll d;ll D; // 2 * 10^5ll coords(ll i, ll j) {return m*i + j;}vll uf_par;vll uf_size;vsp uf_border; // <d,par_id> over all active componentssp best; // <d,par_id> over all active components// best contains the id of where it is, not where it goes.// being an active component is the same as having// an element with your par_id in this set.sp edge; // <d,id> for all things on the edge.int main() {cin >> n;cin >> m;d.resize(n*m,0);rep(i,0,n) {rep(j,0,m) {cin >> d[coords(i,j)];}}D = n*m;// initialize ufuf_par.resize(n*m,0);rep(i,0,n*m) {uf_par[i] = i;}uf_size.resize(n*m,1);uf_border.resize(n*m,sp());rep(i,0,n) {rep(j,0,m) {if (i != 0) {uf_border[coords(i,j)].insert(mp(-d[coords(i-1,j)],coords(i-1,j)));}if (i != n-1) {uf_border[coords(i,j)].insert(mp(-d[coords(i+1,j)],coords(i+1,j)));}if (j != 0) {uf_border[coords(i,j)].insert(mp(-d[coords(i,j-1)],coords(i,j-1)));}if (j != m-1) {uf_border[coords(i,j)].insert(mp(-d[coords(i,j+1)],coords(i,j+1)));}}}// create edgerep(i,0,n) {edge.insert(mp(-d[coords(i,0)],coords(i,0)));}rep(i,0,n) {edge.insert(mp(-d[coords(i,m-1)],coords(i,m-1)));}rep(j,0,m) {edge.insert(mp(-d[coords(0,j)],coords(0,j)));}rep(j,0,m) {edge.insert(mp(-d[coords(n-1,j)],coords(n-1,j)));}best.clear();while (!try_D()) {D--;} // D=1 must always workcout << D << endl;if (debug) {ll counting = 0;rep(i,0,n) {rep(j,0,m) {if (uf_parent(coords(i,j)) == uf_parent(ans)) {counting++;}}}cout << counting << " " << uf_size[ans] << " " << ans << " " << uf_parent(ans) << endl;}return 0;}bool try_D() {while (-(*edge.begin()).first >= D) { // Introduce all edge components with d >= Dll tmp = (*edge.begin()).second;if (uf_par[tmp] == tmp) {best.insert(mp((*uf_border[tmp].begin()).first,tmp));if (uf_border[tmp].empty()) {cout << "oh no" << endl;}}edge.erase(edge.begin()); // Adding item to best is the same as activating it?}while (!best.empty()) {ll cmp = uf_parent((*best.begin()).second);best.erase(best.begin());while (-(*uf_border[cmp].begin()).first >= D - uf_size[cmp]) {ll other = uf_parent((*uf_border[cmp].begin()).second);uf_border[cmp].erase(uf_border[cmp].begin());cmp = uf_merge(cmp, other); // uf_merge deals with if the two are in the same componentif (uf_size[cmp] >= D) {ans = cmp;return true;}} // backburner time!edge.insert(mp((*uf_border[cmp].begin()).first - uf_size[cmp],cmp)); // <-(d+uf_size), par_id>}return false;}ll uf_parent(ll a) {if (uf_par[a] != uf_par[uf_par[a]]) {uf_par[a] = uf_par[uf_par[a]];}return uf_par[a];}ll uf_merge(ll a, ll b) {ll ap = uf_parent(a);ll bp = uf_parent(b);if (ap == bp) {return ap;}if (uf_size[bp] > uf_size[ap]) {swap(ap,bp);}uf_par[bp] = ap;uf_size[ap] += uf_size[bp];if (uf_border[ap].sz() < uf_border[bp].sz()) {swap(uf_border[ap],uf_border[bp]);}uf_border[ap].insert(all(uf_border[bp]));uf_border[bp].clear();return ap;}// We build from larger to smaller, beginning at the edge.// Hence we need to sort all the things at the edge to do// stuff// Consistency stuff:// Everything within a compoent has the same parent// This parent has a set with the cells on the border ordered by d// It may contain cells already in the component, so this needs to be checked in every acess// We want every component to be able to reach D.// Hence it can add a cell iff the new call has d >= D-uf_size[cmp]. D is global. uf_size is consistent// We always try to add the next cell with largest d over all possible merges.// If this wasn't large enough, we put the component on the backburner.// Backburner = components with no immediate possible merges.// What if a new merge becomes possible for a component on the back-burner?// This only happends when another component expands into it.// Then the components will be merged and the non-backburner will keep being a non-backburner.// What happends when all components have been put on the back-burner?// Then we decrement D.// How do we non-linearly get items back from the back-burner?// Can we sort stuff on the back-burner such that some stuff get's back earlier?// Then every thing goes back at most once per item.// Something goes back when it can merge with the item. d_max >= D-uf_size, which happends when D =< d_max + uf_size.// Hence we can use edge as the back_burner.// After we have gone into a component and merged everything there is there,// we add it to the back-burner as it cannot get high enough on the list in this iteration of D// unless another compoennt merges into it, but then we only take over that spot in best.
Test details
Test 1
Group: 1, 5, 6
Verdict: ACCEPTED
input |
---|
4 4 9 11 5 7 7 9 14 3 1 3 2 3 11 4 14 8 |
correct output |
---|
10 |
user output |
---|
10 |
Test 2
Group: 1, 5, 6
Verdict: ACCEPTED
input |
---|
5 3 10 7 11 8 5 5 12 9 10 3 13 9 ... |
correct output |
---|
10 |
user output |
---|
10 |
Test 3
Group: 1, 5, 6
Verdict: ACCEPTED
input |
---|
4 4 3 2 2 2 5 1 1 1 8 4 1 1 7 6 2 1 |
correct output |
---|
8 |
user output |
---|
8 |
Test 4
Group: 1, 5, 6
Verdict: ACCEPTED
input |
---|
3 5 1 11 1 3 5 4 12 7 8 7 13 14 14 9 4 |
correct output |
---|
14 |
user output |
---|
14 |
Test 5
Group: 1, 5, 6
Verdict: ACCEPTED
input |
---|
5 3 11 8 12 11 11 12 6 2 3 11 8 13 ... |
correct output |
---|
12 |
user output |
---|
12 |
Test 6
Group: 1, 5, 6
Verdict: ACCEPTED
input |
---|
3 5 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 |
correct output |
---|
14 |
user output |
---|
14 |
Test 7
Group: 1, 5, 6
Verdict: ACCEPTED
input |
---|
4 4 12 8 6 5 12 9 6 1 10 1 3 2 8 1 1 1 |
correct output |
---|
12 |
user output |
---|
12 |
Test 8
Group: 1, 5, 6
Verdict: ACCEPTED
input |
---|
4 4 8 3 15 14 10 12 2 4 5 16 9 6 7 13 1 11 |
correct output |
---|
13 |
user output |
---|
13 |
Test 9
Group: 1, 2, 5, 6
Verdict: ACCEPTED
input |
---|
4 4 4 1 1 2 3 5 4 2 2 2 1 2 1 4 3 4 |
correct output |
---|
4 |
user output |
---|
4 |
Test 10
Group: 2, 6
Verdict: ACCEPTED
input |
---|
10 20000 5 3 2 1 3 2 3 3 4 5 1 1 2 3 5 ... |
correct output |
---|
5 |
user output |
---|
5 |
Test 11
Group: 2, 6
Verdict: ACCEPTED
input |
---|
10 20000 1 2 1 2 1 2 1 2 1 1 1 1 2 1 1 ... |
correct output |
---|
3 |
user output |
---|
3 |
Test 12
Group: 2, 6
Verdict: ACCEPTED
input |
---|
10 20000 3 2 2 3 1 2 1 4 4 3 1 4 3 2 4 ... |
correct output |
---|
5 |
user output |
---|
5 |
Test 13
Group: 2, 6
Verdict: ACCEPTED
input |
---|
20000 10 1 1 3 1 2 1 1 1 1 1 1 2 2 1 1 1 1 2 1 1 2 1 1 1 2 2 1 1 1 2 1 1 1 1 1 1 1 1 1 1 ... |
correct output |
---|
4 |
user output |
---|
4 |
Test 14
Group: 2, 6
Verdict: ACCEPTED
input |
---|
10 20000 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ... |
correct output |
---|
3 |
user output |
---|
3 |
Test 15
Group: 2, 6
Verdict: ACCEPTED
input |
---|
10 20000 3 1 3 1 2 1 2 3 2 2 1 2 1 1 2 ... |
correct output |
---|
3 |
user output |
---|
3 |
Test 16
Group: 2, 6
Verdict: ACCEPTED
input |
---|
10 20000 1 2 2 2 1 2 3 1 2 2 2 1 2 2 2 ... |
correct output |
---|
4 |
user output |
---|
4 |
Test 17
Group: 2, 6
Verdict: ACCEPTED
input |
---|
10 20000 3 3 2 3 2 3 2 2 2 2 2 1 3 2 1 ... |
correct output |
---|
4 |
user output |
---|
4 |
Test 18
Group: 2, 6
Verdict: ACCEPTED
input |
---|
10 20000 1 3 3 1 1 4 3 3 3 1 2 2 1 3 1 ... |
correct output |
---|
5 |
user output |
---|
5 |
Test 19
Group: 2, 6
Verdict: ACCEPTED
input |
---|
7 28571 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 ... |
correct output |
---|
3 |
user output |
---|
3 |
Test 20
Group: 2, 6
Verdict: ACCEPTED
input |
---|
28571 7 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 ... |
correct output |
---|
5 |
user output |
---|
5 |
Test 21
Group: 2, 6
Verdict: ACCEPTED
input |
---|
447 447 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 ... |
correct output |
---|
3 |
user output |
---|
3 |
Test 22
Group: 3, 4, 5, 6
Verdict: ACCEPTED
input |
---|
1 100 46 23 23 55 37 17 30 32 25 71 ... |
correct output |
---|
30 |
user output |
---|
30 |
Test 23
Group: 3, 4, 5, 6
Verdict: ACCEPTED
input |
---|
1 100 8 13 12 11 15 15 15 19 18 21 2... |
correct output |
---|
76 |
user output |
---|
76 |
Test 24
Group: 3, 4, 5, 6
Verdict: ACCEPTED
input |
---|
1 100 94 94 94 95 95 91 97 100 92 98... |
correct output |
---|
95 |
user output |
---|
95 |
Test 25
Group: 3, 4, 5, 6
Verdict: ACCEPTED
input |
---|
1 100 83 83 83 83 83 83 83 83 83 83 ... |
correct output |
---|
83 |
user output |
---|
83 |
Test 26
Group: 3, 4, 5, 6
Verdict: ACCEPTED
input |
---|
1 100 33 34 35 38 38 40 41 42 42 45 ... |
correct output |
---|
95 |
user output |
---|
95 |
Test 27
Group: 3, 4, 5, 6
Verdict: ACCEPTED
input |
---|
1 100 57 1 80 39 18 63 30 86 85 55 8... |
correct output |
---|
29 |
user output |
---|
29 |
Test 28
Group: 4, 6
Verdict: WRONG ANSWER
input |
---|
1 200000 138736 14949 12344 104147 1333... |
correct output |
---|
1806 |
user output |
---|
1906 |
Test 29
Group: 4, 6
Verdict: ACCEPTED
input |
---|
1 200000 141245 141090 141163 141286 14... |
correct output |
---|
155109 |
user output |
---|
155109 |
Test 30
Group: 4, 6
Verdict: ACCEPTED
input |
---|
1 200000 102358 102469 102440 102402 10... |
correct output |
---|
152388 |
user output |
---|
152388 |
Test 31
Group: 4, 6
Verdict: ACCEPTED
input |
---|
1 200000 180410 160820 160820 180614 18... |
correct output |
---|
160832 |
user output |
---|
160832 |
Test 32
Group: 4, 6
Verdict: ACCEPTED
input |
---|
1 200000 198270 198270 198270 198270 19... |
correct output |
---|
198270 |
user output |
---|
198270 |
Test 33
Group: 4, 6
Verdict: ACCEPTED
input |
---|
1 200000 1 1 3 2 1 1 2 3 6 6 6 7 8 9 10... |
correct output |
---|
199995 |
user output |
---|
199995 |
Test 34
Group: 4, 6
Verdict: WRONG ANSWER
input |
---|
1 200000 14737 162555 44228 170991 1340... |
correct output |
---|
1902 |
user output |
---|
2002 |
Test 35
Group: 5, 6
Verdict: ACCEPTED
input |
---|
31 32 669 792 226 189 860 737 291 83... |
correct output |
---|
565 |
user output |
---|
565 |
Test 36
Group: 5, 6
Verdict: ACCEPTED
input |
---|
10 100 730 698 339 743 536 702 94 556... |
correct output |
---|
529 |
user output |
---|
529 |
Test 37
Group: 5, 6
Verdict: ACCEPTED
input |
---|
32 31 633 613 618 605 635 638 668 67... |
correct output |
---|
678 |
user output |
---|
678 |
Test 38
Group: 5, 6
Verdict: ACCEPTED
input |
---|
142 7 983 930 963 926 979 962 962 966 930 963 924 928 928 926 926 929 929 922 931 931 978 929 929 929 922 959 928 964 ... |
correct output |
---|
934 |
user output |
---|
934 |
Test 39
Group: 5, 6
Verdict: ACCEPTED
input |
---|
31 32 977 977 977 977 977 977 977 97... |
correct output |
---|
977 |
user output |
---|
977 |
Test 40
Group: 5, 6
Verdict: ACCEPTED
input |
---|
50 20 1 27 14 23 38 48 56 3 12 9 6 2... |
correct output |
---|
997 |
user output |
---|
997 |
Test 41
Group: 5, 6
Verdict: ACCEPTED
input |
---|
20 50 481 532 624 290 965 58 448 872... |
correct output |
---|
504 |
user output |
---|
504 |
Test 42
Group: 6
Verdict: ACCEPTED
input |
---|
447 447 6474 27185 108482 124481 16058... |
correct output |
---|
88202 |
user output |
---|
88202 |
Test 43
Group: 6
Verdict: ACCEPTED
input |
---|
1000 200 27722 57131 197677 184858 9285... |
correct output |
---|
89324 |
user output |
---|
89324 |
Test 44
Group: 6
Verdict: ACCEPTED
input |
---|
447 447 70928 73154 72640 74764 75237 ... |
correct output |
---|
181096 |
user output |
---|
181096 |
Test 45
Group: 6
Verdict: ACCEPTED
input |
---|
7 28571 193031 185883 171670 185794 17... |
correct output |
---|
171680 |
user output |
---|
171680 |
Test 46
Group: 6
Verdict: ACCEPTED
input |
---|
10 20000 191628 191628 191628 191628 19... |
correct output |
---|
191628 |
user output |
---|
191628 |
Test 47
Group: 6
Verdict: ACCEPTED
input |
---|
200 1000 3550 2640 3791 4248 4257 4504 ... |
correct output |
---|
199997 |
user output |
---|
199997 |
Test 48
Group: 6
Verdict: ACCEPTED
input |
---|
1000 200 198379 62425 88013 50967 49098... |
correct output |
---|
89131 |
user output |
---|
89131 |