Submission #31820

#	Time	Username	Problem	Language	Result	Execution time	Memory
31820		top34051	Sorting (IOI15_sorting)	C++14	74 / 100	47 ms	10288 KiB

sorting

#include "sorting.h"
#include<bits/stdc++.h>
using namespace std;
#define maxn 2005

int n, s[maxn];
int a[maxn], pos[maxn];
pair<int,int> sw[maxn];

int get(int rec) {
    int i,x,cnt;
    for(i=0;i<n;i++) a[i] = s[i];
    for(i=0;i<n;i++) pos[a[i]] = i;
    cnt = 0;
    for(i=0;i<n;i++) {
        x = pos[i];
        if(i!=x) {
            pos[a[i]] = x;
            swap(a[i], a[x]);
            if(rec) sw[cnt] = {a[i],a[x]};
            cnt++;
        }
    }
    return cnt;
}

int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
    int i,x,now;
    n = N;
    for(i=0;i<n;i++) s[i] = S[i];
    for(now=-1;now<M;now++) {
        if(now>=0) swap(s[X[now]],s[Y[now]]);
        if(get(0)<=now+1) break;
    }
    get(1);
    for(i=0;i<n;i++) s[i] = S[i];
    for(i=0;i<now+1;i++) {
        swap(s[X[i]], s[Y[i]]);
//        printf("i = %d : {%d, %d}\n",i,sw[i].first,sw[i].second);
        for(x=0;x<n;x++) {
            if(s[x]==sw[i].first) P[i] = x;
            if(s[x]==sw[i].second) Q[i] = x;
        }
        swap(s[P[i]], s[Q[i]]);
    }
    return now+1;
}

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