Submission #341991

#	Time	Username	Problem	Language	Result	Execution time	Memory
341991		Marlov	Ancient Books (IOI17_books)	C++14	0 / 100	1 ms	384 KiB

books

/*
Code by @marlov       
*/
#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include <vector>
#include <string>
#include <cmath>
#include <algorithm>
#include <iomanip>
#include <utility>
#include <set>
#include <unordered_set>
#include <map>
#include <unordered_map>
#include <stack>
#include <queue>
#include <iterator>
#include <bitset>
using namespace std;
typedef long long ll;
typedef pair<long long,long long> ii;

#define maxN 1000005
#define INF 1000000000

long long N;
bool visited[maxN];
vector<int> child;
long long root;
long long cg=-1;
long long td[maxN];

vector<vector<ll> > grps;

void dfs(long long n){
	if(visited[n]) return;
	visited[n]=true;
	grps.back().push_back(n);
	td[cg]+=abs(n-child[n]);
	long long tr=n-root;


	dfs(child[n]);
}


//need to fix min distance to do all things
int minimum_walk(vector<int> p, int s){
	N=p.size();
	child=p;
	root=s;

	for(long long i=0;i<N;i++){
		if(!visited[i]){
			cg++;
			grps.push_back(vector<ll>());
			dfs(i);
		}
	}
	int result=0;
	//vector<pi> dist;
	for(int i=0;i<=cg;i++){
		int mind=INF;
		for(int a:grps[i]){
			mind=min(a,mind);
		}
		result+=2*mind+td[i];
	}
	return result;
}
/*
int main() {
	ios_base::sync_with_stdio(0); cin.tie(0);
	cout<<minimum_walk({0,2,3,1},0);
    return 0;
}
*/


/* stuff you should look for
	* long long overflow, array bounds
	* special cases (n=1,n=0?)
	* do smth instead of nothing and stay organized
*/

Compilation message (stderr)

books.cpp: In function 'void dfs(long long int)':
books.cpp:43:12: warning: unused variable 'tr' [-Wunused-variable]
   43 |  long long tr=n-root;
      |            ^~

• Subtask 1: 0 / 12
• Subtask 2: 0 / 10
• Subtask 3: 0 / 28
• Subtask 4: 0 / 20
• Subtask 5: 0 / 30