oj.uz

Submission #609700

# Submission time Handle Problem Language Result Execution time Memory
609700 2022-07-27T19:27:25 Z dnass Ancient Books (IOI17_books) C++17
100 / 100
 390 ms 124528 KB 
#include "books.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long int lld;
#define INF 1000000000000000000LL
#define ff first
#define ss second

lld n;
lld comps;
lld cyc[1000100];
vector<vector<lld>> cycles;
pair<pair<lld,lld>,pair<lld,lld>> reach[1000100];
lld lfinal, rfinal;
lld par[1000100], sz[1000100];

lld find(lld x){
	if(x==par[x]) return x;
	return par[x] = find(par[x]);
}

void uni(lld a, lld b){
	a = find(a);
	b = find(b);
	if(a==b) return;
	if(sz[a]>sz[b]) swap(a,b);
	sz[b] += sz[a];
	par[a] = b;
}

bool cmp(lld comp1, lld comp2){
	return reach[comp1].ss.ff<reach[comp2].ss.ff;
}

void debug(){
	for(lld i=0;i<n;i++) cout << find(cyc[i]) << " \n"[i==n-1];
	for(lld i=0;i<comps;i++)
		if((lld)cycles[i].size()>1) cout << i << ": " << reach[i].ff.ff << " " << reach[i].ff.ss << " " << reach[i].ss.ff << " " << reach[i].ss.ss << "\n";
}

lld minimum_walk(vector<int> p, int s){
	n = (lld) p.size();
	lld ans = 0;
	for(lld i=0;i<n;i++) ans+=abs(p[i]-i);
	for(lld i=0;i<n;i++){
		par[i] = i;
		sz[i] = 1;
	}
	vector<bool> vis(n, false);
	comps = 0;
	lfinal = s, rfinal = s;
	for(lld i=0;i<n;i++){
		if(!vis[i]){
			vector<lld> tmp;
			lld x = i;
			while(true){
				if(vis[x]) break;
				tmp.push_back(x);
				vis[x] = true;
				cyc[x] = comps;
				x = p[x];
			}
			sort(tmp.begin(), tmp.end());
			cycles.push_back(tmp);
			if((int)tmp.size()>1){
				if(tmp.front()>=s) reach[comps] = {{tmp.front(),-1},{tmp.front(),tmp.back()}};
				else if(tmp.back()<=s) reach[comps] = {{tmp.front(),tmp.back()},{INF,tmp.back()}};
				else{
					auto it = lower_bound(tmp.begin(), tmp.end(), s);
					reach[comps] = {{tmp.front(),*prev(it)},{*it,tmp.back()}};
				}
				lfinal = min(lfinal, reach[comps].ff.ff);
				rfinal = max(rfinal, reach[comps].ss.ss);
			}else{
				reach[comps] = {{tmp[0],tmp[0]},{tmp[0],tmp[0]}};
			}
			comps++;
		}
	}
	lld cur_comp = find(cyc[s]);
	lld lblock = s, rblock = s;
	lld lblocknew = reach[cur_comp].ff.ff, rblocknew = reach[cur_comp].ss.ss;
	while(lblocknew!=lblock||rblocknew!=rblock){
		lld lblocknewnew, rblocknewnew;
		for(lld i=lblocknew;i<=lblock;i++){
			if((lld)cycles[find(cyc[i])].size()==1) continue;
			reach[cur_comp].ff.ff = min(reach[cur_comp].ff.ff, reach[find(cyc[i])].ff.ff);
			reach[cur_comp].ff.ss = max(reach[cur_comp].ff.ss, reach[find(cyc[i])].ff.ss);
			reach[cur_comp].ss.ff = min(reach[cur_comp].ss.ff, reach[find(cyc[i])].ss.ff);
			reach[cur_comp].ss.ss = max(reach[cur_comp].ss.ss, reach[find(cyc[i])].ss.ss);
			lblocknewnew = reach[cur_comp].ff.ff;
			rblocknewnew = reach[cur_comp].ss.ss;
			uni(cyc[i], cur_comp);
			cyc[i] = cur_comp;
		}
		for(lld i=rblock;i<=rblocknew;i++){
			if((lld)cycles[find(cyc[i])].size()==1) continue;
			reach[cur_comp].ff.ff = min(reach[cur_comp].ff.ff, reach[find(cyc[i])].ff.ff);
			reach[cur_comp].ff.ss = max(reach[cur_comp].ff.ss, reach[find(cyc[i])].ff.ss);
			reach[cur_comp].ss.ff = min(reach[cur_comp].ss.ff, reach[find(cyc[i])].ss.ff);
			reach[cur_comp].ss.ss = max(reach[cur_comp].ss.ss, reach[find(cyc[i])].ss.ss);
			lblocknewnew = reach[cur_comp].ff.ff;
			rblocknewnew = reach[cur_comp].ss.ss;
			uni(cyc[i], cur_comp);
			cyc[i] = cur_comp;
		}
		lblock = lblocknew; rblock = rblocknew;
		lblocknew = lblocknewnew; rblocknew = rblocknewnew;
	}
	lld l = INF;
	for(lld i=lblock-1;i>=lfinal;i--){
		if((lld)cycles[find(cyc[i])].size()==1) continue;
		if(i<l){
			cur_comp = find(cyc[i]);
			l = reach[cur_comp].ff.ff;
		}else{
			reach[cur_comp].ff.ff = min(reach[cur_comp].ff.ff, reach[find(cyc[i])].ff.ff);
			reach[cur_comp].ff.ss = max(reach[cur_comp].ff.ss, reach[find(cyc[i])].ff.ss);
			reach[cur_comp].ss.ff = min(reach[cur_comp].ss.ff, reach[find(cyc[i])].ss.ff);
			reach[cur_comp].ss.ss = max(reach[cur_comp].ss.ss, reach[find(cyc[i])].ss.ss);
			l = reach[cur_comp].ff.ff;
			uni(cyc[i], cur_comp);
			cyc[i] = cur_comp;
		}
	}
	lld r = -1;
	for(lld i=rblock+1;i<=rfinal;i++){
		if((lld)cycles[find(cyc[i])].size()==1) continue;
		if(i>r){
			cur_comp = find(cyc[i]);
			r = reach[cur_comp].ss.ss;
		}else{
			reach[cur_comp].ff.ff = min(reach[cur_comp].ff.ff, reach[find(cyc[i])].ff.ff);
			reach[cur_comp].ff.ss = max(reach[cur_comp].ff.ss, reach[find(cyc[i])].ff.ss);
			reach[cur_comp].ss.ff = min(reach[cur_comp].ss.ff, reach[find(cyc[i])].ss.ff);
			reach[cur_comp].ss.ss = max(reach[cur_comp].ss.ss, reach[find(cyc[i])].ss.ss);
			r = reach[cur_comp].ss.ss;
			uni(cyc[i], cur_comp);
			cyc[i] = cur_comp;
		}
	}
	//debug();
	set<lld> brid;
	for(lld i=0;i<n;i++){
		if((lld)cycles[find(cyc[i])].size()==1) continue;
		if(reach[find(cyc[i])].ff.ff<s&&reach[find(cyc[i])].ss.ss>s) brid.insert(find(cyc[i]));
	}
	vector<lld> bridges;
	for(lld xxx:brid) bridges.push_back(xxx);
	sort(bridges.begin(), bridges.end(), cmp);
	for(lld i=1;i<(lld)bridges.size();i++){
		if(reach[bridges[i-1]].ss.ss>reach[bridges[i]].ss.ff||reach[bridges[i-1]].ff.ff<reach[bridges[i]].ff.ss){
			reach[find(bridges[i-1])].ff.ff = min(reach[find(bridges[i-1])].ff.ff, reach[find(bridges[i])].ff.ff);
			reach[find(bridges[i-1])].ff.ss = max(reach[find(bridges[i-1])].ff.ss, reach[find(bridges[i])].ff.ss);
			reach[find(bridges[i-1])].ss.ff = min(reach[find(bridges[i-1])].ss.ff, reach[find(bridges[i])].ss.ff);
			reach[find(bridges[i-1])].ss.ss = max(reach[find(bridges[i-1])].ss.ss, reach[find(bridges[i])].ss.ss);
			reach[find(bridges[i])] = reach[find(bridges[i-1])];
			uni(bridges[i-1], bridges[i]);
		}
	}
	l = lblock, r = rblock;
	while(l>lfinal||r<rfinal){
		lld i, j;
		lld lpath = (l-1<lfinal?INF:0), rpath = (r+1>rfinal?INF:0);
		bool found_bridge = false;
		for(i=l-1;i>=lfinal;i--){
			if(reach[find(cyc[i])].ff.ff<s&&reach[find(cyc[i])].ss.ss>s){
				lpath+=2;
				found_bridge = true;
				break;
			}
			if(find(cyc[i])!=find(cyc[i+1])) lpath+=2;
			i = reach[find(cyc[i])].ff.ff;
			if(i==lfinal) break;
		}
		for(j=r+1;j<=rfinal;j++){
			if(reach[find(cyc[j])].ff.ff<s&&reach[find(cyc[j])].ss.ss>s){
				found_bridge = true;
				rpath+=2;
				break;
			}
			if(find(cyc[j])!=find(cyc[j-1])) rpath+=2;
			j = reach[find(cyc[j])].ss.ss;
			if(j==rfinal) break;
		}
		if(found_bridge) ans += min(lpath, rpath);
		else ans += (lpath==INF?0:lpath)+(rpath==INF?0:rpath);
		if(l-1>=lfinal)l = reach[find(cyc[i])].ff.ff;
		if(r+1<=rfinal)r = reach[find(cyc[j])].ss.ss;
		//printf("------------\n%lld %lld\n--------------\n",l,r);
	}
	return ans;
}

Compilation message

books.cpp: In function 'lld minimum_walk(std::vector<int>, int)':
books.cpp:83:36: warning: 'rblocknewnew' may be used uninitialized in this function [-Wmaybe-uninitialized]
   83 |  while(lblocknew!=lblock||rblocknew!=rblock){
      |                           ~~~~~~~~~^~~~~~~~
books.cpp:83:17: warning: 'lblocknewnew' may be used uninitialized in this function [-Wmaybe-uninitialized]
   83 |  while(lblocknew!=lblock||rblocknew!=rblock){
      |        ~~~~~~~~~^~~~~~~~

Subtask #1
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 316 KB Output is correct
3 Correct 1 ms 320 KB Output is correct
4 Correct 1 ms 316 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 312 KB Output is correct
7 Correct 1 ms 316 KB Output is correct
8 Correct 1 ms 320 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 312 KB Output is correct
14 Correct 1 ms 316 KB Output is correct
15 Correct 1 ms 212 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 320 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 316 KB Output is correct
3 Correct 1 ms 320 KB Output is correct
4 Correct 1 ms 316 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 312 KB Output is correct
7 Correct 1 ms 316 KB Output is correct
8 Correct 1 ms 320 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 312 KB Output is correct
14 Correct 1 ms 316 KB Output is correct
15 Correct 1 ms 212 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 320 KB Output is correct
19 Correct 1 ms 316 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
21 Correct 1 ms 340 KB Output is correct
22 Correct 1 ms 320 KB Output is correct
23 Correct 1 ms 316 KB Output is correct
24 Correct 1 ms 340 KB Output is correct
25 Correct 1 ms 340 KB Output is correct
26 Correct 1 ms 340 KB Output is correct
27 Correct 1 ms 340 KB Output is correct
28 Correct 1 ms 340 KB Output is correct
29 Correct 1 ms 320 KB Output is correct

Subtask #3
28.0 / 28.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 316 KB Output is correct
3 Correct 1 ms 320 KB Output is correct
4 Correct 1 ms 316 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 312 KB Output is correct
7 Correct 1 ms 316 KB Output is correct
8 Correct 1 ms 320 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 312 KB Output is correct
14 Correct 1 ms 316 KB Output is correct
15 Correct 1 ms 212 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 320 KB Output is correct
19 Correct 1 ms 316 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
21 Correct 1 ms 340 KB Output is correct
22 Correct 1 ms 320 KB Output is correct
23 Correct 1 ms 316 KB Output is correct
24 Correct 1 ms 340 KB Output is correct
25 Correct 1 ms 340 KB Output is correct
26 Correct 1 ms 340 KB Output is correct
27 Correct 1 ms 340 KB Output is correct
28 Correct 1 ms 340 KB Output is correct
29 Correct 1 ms 320 KB Output is correct
30 Correct 295 ms 50732 KB Output is correct
31 Correct 295 ms 47948 KB Output is correct
32 Correct 270 ms 124528 KB Output is correct
33 Correct 251 ms 98528 KB Output is correct
34 Correct 241 ms 98572 KB Output is correct
35 Correct 259 ms 96748 KB Output is correct
36 Correct 239 ms 64636 KB Output is correct
37 Correct 198 ms 48920 KB Output is correct
38 Correct 220 ms 46788 KB Output is correct
39 Correct 222 ms 46696 KB Output is correct
40 Correct 218 ms 46376 KB Output is correct
41 Correct 273 ms 47132 KB Output is correct
42 Correct 220 ms 47064 KB Output is correct
43 Correct 244 ms 102220 KB Output is correct

Subtask #4
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 320 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 320 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 1 ms 316 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 1 ms 440 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 316 KB Output is correct
13 Correct 1 ms 340 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 340 KB Output is correct
17 Correct 1 ms 340 KB Output is correct
18 Correct 1 ms 340 KB Output is correct
19 Correct 1 ms 340 KB Output is correct
20 Correct 1 ms 316 KB Output is correct

Subtask #5
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 316 KB Output is correct
3 Correct 1 ms 320 KB Output is correct
4 Correct 1 ms 316 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 312 KB Output is correct
7 Correct 1 ms 316 KB Output is correct
8 Correct 1 ms 320 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 312 KB Output is correct
14 Correct 1 ms 316 KB Output is correct
15 Correct 1 ms 212 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 320 KB Output is correct
19 Correct 1 ms 316 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
21 Correct 1 ms 340 KB Output is correct
22 Correct 1 ms 320 KB Output is correct
23 Correct 1 ms 316 KB Output is correct
24 Correct 1 ms 340 KB Output is correct
25 Correct 1 ms 340 KB Output is correct
26 Correct 1 ms 340 KB Output is correct
27 Correct 1 ms 340 KB Output is correct
28 Correct 1 ms 340 KB Output is correct
29 Correct 1 ms 320 KB Output is correct
30 Correct 295 ms 50732 KB Output is correct
31 Correct 295 ms 47948 KB Output is correct
32 Correct 270 ms 124528 KB Output is correct
33 Correct 251 ms 98528 KB Output is correct
34 Correct 241 ms 98572 KB Output is correct
35 Correct 259 ms 96748 KB Output is correct
36 Correct 239 ms 64636 KB Output is correct
37 Correct 198 ms 48920 KB Output is correct
38 Correct 220 ms 46788 KB Output is correct
39 Correct 222 ms 46696 KB Output is correct
40 Correct 218 ms 46376 KB Output is correct
41 Correct 273 ms 47132 KB Output is correct
42 Correct 220 ms 47064 KB Output is correct
43 Correct 244 ms 102220 KB Output is correct
44 Correct 1 ms 320 KB Output is correct
45 Correct 1 ms 340 KB Output is correct
46 Correct 1 ms 340 KB Output is correct
47 Correct 1 ms 320 KB Output is correct
48 Correct 1 ms 340 KB Output is correct
49 Correct 1 ms 340 KB Output is correct
50 Correct 1 ms 340 KB Output is correct
51 Correct 1 ms 316 KB Output is correct
52 Correct 1 ms 340 KB Output is correct
53 Correct 1 ms 440 KB Output is correct
54 Correct 1 ms 340 KB Output is correct
55 Correct 1 ms 316 KB Output is correct
56 Correct 1 ms 340 KB Output is correct
57 Correct 1 ms 340 KB Output is correct
58 Correct 1 ms 340 KB Output is correct
59 Correct 1 ms 340 KB Output is correct
60 Correct 1 ms 340 KB Output is correct
61 Correct 1 ms 340 KB Output is correct
62 Correct 1 ms 340 KB Output is correct
63 Correct 1 ms 316 KB Output is correct
64 Correct 245 ms 102312 KB Output is correct
65 Correct 243 ms 108504 KB Output is correct
66 Correct 191 ms 48936 KB Output is correct
67 Correct 183 ms 47568 KB Output is correct
68 Correct 21 ms 6904 KB Output is correct
69 Correct 20 ms 5836 KB Output is correct
70 Correct 21 ms 7948 KB Output is correct
71 Correct 26 ms 11268 KB Output is correct
72 Correct 23 ms 11388 KB Output is correct
73 Correct 20 ms 4816 KB Output is correct
74 Correct 244 ms 98572 KB Output is correct
75 Correct 234 ms 98540 KB Output is correct
76 Correct 241 ms 101276 KB Output is correct
77 Correct 298 ms 101932 KB Output is correct
78 Correct 233 ms 94544 KB Output is correct
79 Correct 258 ms 94660 KB Output is correct
80 Correct 216 ms 124528 KB Output is correct
81 Correct 351 ms 103816 KB Output is correct
82 Correct 390 ms 103912 KB Output is correct
83 Correct 221 ms 75096 KB Output is correct
84 Correct 224 ms 69952 KB Output is correct
85 Correct 186 ms 57992 KB Output is correct
86 Correct 190 ms 50296 KB Output is correct
87 Correct 292 ms 121852 KB Output is correct
88 Correct 259 ms 105076 KB Output is correct
89 Correct 246 ms 82132 KB Output is correct
90 Correct 175 ms 47680 KB Output is correct
91 Correct 184 ms 46844 KB Output is correct
92 Correct 192 ms 46584 KB Output is correct