Submission #105028

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
105028	2019-04-10T08:28:23 Z	bert30702	Ancient Books (IOI17_books)	C++17	Compilation error	0 ms	0 KB

books

    #include <bits/stdc++.h>
    #include "books.h"
    #define pii pair<int, int>
    #define F first
    #define S second
    using namespace std;
    const int MX = 1e6 + 100;
    int boss[MX];
    int Find(int u) {
    	return boss[u] == u ? u : boss[u] = Find(boss[u]);
    }
    void merge(int a, int b) {
    	boss[Find(a)] = Find(b);
    }
    priority_queue<int> pq[MX];
    long long minimun_walk(vector<int> p, int s) {
    	long long sum = 0;
    	for(int i = 0; i < p.size(); i ++) boss[i] = i;
    	for(int i = 0; i < p.size(); i ++) sum += abs(i - p[i]), merge(i, p[i]);
    	for(int i = 0; i < p.size(); i ++) pq[Find(i)].push(i); 
    	multiset<pii> ms;
    	for(int i = 0; i < p.size(); i ++) {
    		if(i == Find(i)) ms.insert({pq[i].top(), i}); 
    	}
    	long long ans = 1ll << 60;
    	for(int i = p.size() - 1; i >= 0; i --) {
    		int a = (--ms.end()) -> F;
    		int b = (ms.begin()) -> F;
    		if((a > s and b > s) or (a < s and b < s)) {
    			ans = min(ans, sum + max(abs(s - a), abs(s - b)) * 2);
    		}
    		else {
    			ans = min(ans, sum + (a - b) * 2);
    		}
    		if((--ms.end()) -> F == i) {
    			int ptr = (--ms.end()) -> S;
    			ms.erase(--ms.end());
    			pq[ptr].pop();
    			if(pq[ptr].size()) ms.insert({pq[ptr].top(), ptr});
    			else return ans;
    		}
    	}
    }

Compilation message

books.cpp: In function 'long long int minimun_walk(std::vector<int>, int)':
books.cpp:18:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
      for(int i = 0; i < p.size(); i ++) boss[i] = i;
                     ~~^~~~~~~~~~
books.cpp:19:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
      for(int i = 0; i < p.size(); i ++) sum += abs(i - p[i]), merge(i, p[i]);
                     ~~^~~~~~~~~~
books.cpp:20:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
      for(int i = 0; i < p.size(); i ++) pq[Find(i)].push(i); 
                     ~~^~~~~~~~~~
books.cpp:22:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
      for(int i = 0; i < p.size(); i ++) {
                     ~~^~~~~~~~~~
books.cpp:43:5: warning: control reaches end of non-void function [-Wreturn-type]
     }
     ^
/tmp/ccS2Q6eY.o: In function `main':
grader.cpp:(.text.startup+0x23a): undefined reference to `minimum_walk(std::vector<int, std::allocator<int> >, int)'
collect2: error: ld returned 1 exit status