# | Submission time | Handle | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
921978 | 2024-02-04T15:41:53 Z | coding_snorlax | Sorting (IOI15_sorting) | C++14 | 0 ms | 0 KB |
#include "sorting.h" #include<bits/stdc++.h> using namespace std; int Answer[10000],vis[10000],Goal[10000],inv_S[10000]; int n; set<int> OK; int Count_cycle(int S[]){ for(int i=0;i<n;i++){ vis[i]=0; } for(int i=0;i<n;i++){ Goal[S[i]]=Answer[i]; } int answer = n; for(int i=0;i<n;i++){ if(!vis[i]){ vis[i]=1; int st = i,now = i; while(Goal[now]!=st){ now = Goal[now]; vis[now]=1; } answer-=1; } } return answer; } void find_Sol(int P[],int Q[],int S[],int ope){ for(int i=0;i<n;i++){ if(S[i]!=Answer[i]){ int j = inv_S[Answer[i]]; inv_S[S[j]]=i; inv_S[S[i]]=j; P[ope]=i; Q[ope]=j; S[j]=S[i]; S[i]=Answer[i]; return; } } P[ope]=0;Q[ope]=0; } int Check(int k,int S[],int X[],int Y[]){ for(int i=0;i<n;i++){ Answer[i]=i; } for(int i=k-1;i>=0;i--){ int tmp = Answer[X[i]]; Answer[X[i]]=Answer[Y[i]]; Answer[Y[i]]=tmp; } if(Count_cycle(S)<=k) return 1; else return 0; } int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) { n=N; int L = 0,R = N; while(L!=R){ int m = (L+R)/2; if(Check(m,S,X,Y)) R=m; else L=m+1; } Check(L,S,X,Y); for(int i=0;i<N;i++){ inv_S[S[i]]=i; } for(int i=0;i<L;i++){ int tmp = S[X[i]]; inv_S[S[X[i]]]=Y[i]; inv_S[S[Y[i]]]=X[i]; S[X[i]]=S[Y[i]]; S[Y[i]]=tmp; tmp = Answer[X[i]]; Answer[X[i]]=Answer[Y[i]]; Answer[Y[i]]=tmp; debug(); find_Sol(P,Q,S,i); } return L; }