Submission #31814

#	Time	Username	Problem	Language	Result	Execution time	Memory
31814		top34051	Sorting (IOI15_sorting)	C++14	20 / 100	3 ms	384 KiB

sorting

#include "sorting.h"
#include<bits/stdc++.h>
using namespace std;
#define maxn 200005

int a[maxn], pos[maxn];

int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
    int i,x,l,r,mid,cnt;
    int ans;
    l = -1; r = M-1;
    while(l<=r) {
        mid = (l+r)/2;
//        printf("MID = %d\n",mid);
        //Init
        for(i=0;i<N;i++) a[i] = S[i];
        for(i=0;i<=mid;i++) swap(a[X[i]], a[Y[i]]);
        for(i=0;i<N;i++) pos[a[i]] = i;
        //Count
        cnt = 0;
        for(i=0;i<N;i++) {
            x = pos[i];
            if(i!=x) {
                pos[a[i]] = x;
//                printf("------ swap %d %d\n",i,x);
                swap(a[i], a[x]);
                cnt++;
            }
        }
        //Check
        if(cnt<=mid+1) {
            ans = mid;
            r = mid-1;
        }
        else l = mid+1;
    }
    //Init
    for(i=0;i<N;i++) a[i] = S[i];
    for(i=0;i<=ans;i++) swap(a[X[i]], a[Y[i]]);
    for(i=0;i<N;i++) pos[a[i]] = i;
    //Count
    cnt = 0;
    for(i=0;i<N;i++) {
        x = pos[i];
        if(i!=x) {
            pos[a[i]] = x;
//            printf("------ swap %d %d\n",i,x);
            swap(a[i], a[x]);
            P[cnt] = i; Q[cnt] = x;
            cnt++;
        }
    }
    while(cnt<=ans) P[cnt] = Q[cnt] = 0, cnt++;
    return ans+1;
}

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