Submission #257857

#	Time	Username	Problem	Language	Result	Execution time	Memory
257857		shrek12357	Sorting (IOI15_sorting)	C++14	0 / 100	2 ms	512 KiB

sorting

#include<bits/stdc++.h> //:3
using namespace std;
typedef long long ll;
#define all(a) (a).begin(), (a).end()
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define rc(s) return cout<<s,0
#define pi pair <int, int>
#define sz(x) (int)((x).size())
#include "sorting.h"
 
const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};
 
const ll H = 1e6 + 11;
 
//ifstream in(".in");
//ofstream out(".out");
 
int pos[H], n, m;
pi query[H], ans[H], a[H];
 
vector<pair<int, int>> toChange;
vector<int> xAns, yAns;
 
bool check(int mid, int nums[], int n, int x[], int y[]) {
  int in[n + 11], out[n + 11];
 
    for(int i = 0; i < n; i++){
        in[i] = out[i] = nums[i];
    }
 
    for(int i = 0; i < mid; i++){
        swap(out[query[i].first], out[query[i].second]);
    }
	int adjList[n + 5]; // can optimize later
	for (int i = 0; i < n; i++) {
		adjList[i] = nums[i];
	}
	bool viz[n + 5];
	for (int i = 0; i < n; i++) {
		viz[i] = false;
	}
 
	int k = 0;
    for(int i = 0; i < n; i++){
 
        if(viz[i])continue;
 
        vector<int>cur;
 
        int v = out[i];
        while(v != i){
            cur.push_back(v);
            v = out[v];
        }
        cur.push_back(v);
 
        for(int j = sz(cur) - 1; j > 0; j--){
            a[k++] = {cur[0], cur[j]};
        }
 
        for(auto it : cur)viz[it] = 1;
    }
 
	if(k > mid)	return false;
  
  	for (int i = 0; i < n; ++i){
        pos[in[i]] = i;
    }
 
    for(int i = 0; i < k; i++){
 
        //His move
        int x = query[i].ff, y = query[i].ss;
        swap(in[x], in[y]);
        pos[in[x]] = x;
        pos[in[y]] = y;
 
        //My move
        x = pos[a[i].ff], y = pos[a[i].ss];
        swap(in[x], in[y]);
        pos[in[x]] = x;
        pos[in[y]] = y;
 
        ans[i] = {x, y};
    }
 
    while(k < mid)ans[k++] = {0, 0};
 
    return 1;
}
 
int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
	int lo = -1;
	int hi = M;
	while (lo + 1 < hi) {
		int mid = (lo + hi) / 2;
		if (check(mid,S,N,X,Y)) {
			hi = mid;
		}
		else {
			lo = mid;
		}
		//toChange.clear();
	}
	check(hi, S, N, X, Y);
	//getAns(hi, S, N, X, Y);
	for (int i = 0; i < xAns.size(); i++) {
		P[i] = xAns[i];
		Q[i] = yAns[i];
	}
	return hi;
}

Compilation message (stderr)

sorting.cpp: In function 'bool check(int, int*, int, int*, int*)':
sorting.cpp:28:56: warning: declaration of 'n' shadows a global declaration [-Wshadow]
 bool check(int mid, int nums[], int n, int x[], int y[]) {
                                                        ^
sorting.cpp:22:13: note: shadowed declaration is here
 int pos[H], n, m;
             ^
sorting.cpp:77:13: warning: declaration of 'int x' shadows a parameter [-Wshadow]
         int x = query[i].ff, y = query[i].ss;
             ^
sorting.cpp:28:46: note: shadowed declaration is here
 bool check(int mid, int nums[], int n, int x[], int y[]) {
                                              ^
sorting.cpp:77:30: warning: declaration of 'int y' shadows a parameter [-Wshadow]
         int x = query[i].ff, y = query[i].ss;
                              ^
sorting.cpp:28:55: note: shadowed declaration is here
 bool check(int mid, int nums[], int n, int x[], int y[]) {
                                                       ^
sorting.cpp:38:6: warning: variable 'adjList' set but not used [-Wunused-but-set-variable]
  int adjList[n + 5]; // can optimize later
      ^~~~~~~
sorting.cpp:28:46: warning: unused parameter 'x' [-Wunused-parameter]
 bool check(int mid, int nums[], int n, int x[], int y[]) {
                                              ^
sorting.cpp:28:55: warning: unused parameter 'y' [-Wunused-parameter]
 bool check(int mid, int nums[], int n, int x[], int y[]) {
                                                       ^
sorting.cpp: In function 'int findSwapPairs(int, int*, int, int*, int*, int*, int*)':
sorting.cpp:111:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < xAns.size(); i++) {
                  ~~^~~~~~~~~~~~~

• Subtask 1: 0 / 8
• Subtask 2: 0 / 12
• Subtask 3: 0 / 16
• Subtask 4: 0 / 18
• Subtask 5: 0 / 20
• Subtask 6: 0 / 26