CSES - Putka Open 2020 – 1/5 - Results
Submission details
Task:Vaihdot
Sender:tykkipeli
Submission time:2020-09-06 03:04:32 +0300
Language:C++11
Status:READY
Result:100
Feedback
groupverdictscore
#1ACCEPTED13
#2ACCEPTED23
#3ACCEPTED64
Test results
testverdicttimegroup
#1ACCEPTED0.01 s1, 2, 3details
#2ACCEPTED0.01 s1, 2, 3details
#3ACCEPTED0.01 s1, 2, 3details
#4ACCEPTED0.01 s1, 2, 3details
#5ACCEPTED0.01 s1, 2, 3details
#6ACCEPTED0.01 s1, 2, 3details
#7ACCEPTED0.01 s1, 2, 3details
#8ACCEPTED0.01 s1, 2, 3details
#9ACCEPTED0.01 s2, 3details
#10ACCEPTED0.01 s2, 3details
#11ACCEPTED0.01 s2, 3details
#12ACCEPTED0.01 s2, 3details
#13ACCEPTED0.01 s2, 3details
#14ACCEPTED0.01 s2, 3details
#15ACCEPTED0.01 s2, 3details
#16ACCEPTED0.01 s2, 3details
#17ACCEPTED0.07 s3details
#18ACCEPTED0.13 s3details
#19ACCEPTED0.10 s3details
#20ACCEPTED0.10 s3details
#21ACCEPTED0.10 s3details
#22ACCEPTED0.11 s3details
#23ACCEPTED0.15 s3details
#24ACCEPTED0.15 s3details

Code

#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;

int a[1000000];
bool seen[1000000];
int inv[1000000];
int cntIso[1000000];
int cntPieni[1000000];

int solve(int n) {
    int ans = 0;
    for (int i = 1; i <= n; i++) seen[i] = false;
    for (int i = 1; i <= n; i++) {
        if (a[i] == 1 || !seen[a[i]-1]) ans++;
        seen[a[i]] = true;
    }
    return ans;
}

bool identity(int n) {
    for (int i = 2; i <= n; i++) {
        if (a[i] != a[i-1]+1) return false;
    }
    return true;
}


#define N (1<<18)
ll p[2*N];

void muuta(int k, int x) {
    k += N;
    p[k] += x;
    for (k /= 2; k >= 1; k /= 2) {
        p[k] = p[2*k]+p[2*k+1];
    }
}

void muutavali(int a, int b, int x) {
    if (a > b) return;
    muuta(a,x);
    muuta(b+1, -x);
}

ll summa(int a, int b) {
    a += N;
    b += N;
    ll s = 0;
    while (a <= b) {
        if (a%2 == 1) s += p[a++];
        if (b%2 == 0) s += p[b--];
        a /= 2; b /= 2;
    }
    return s;
}

int apu[1000000];

void muunna(int n) {
    for (int i = 0; i <= n+1; i++) apu[i] = a[n+1-i];
    for (int i = 0; i <= n+1; i++) a[i] = apu[i];
    for (int i = 0; i <= n+1; i++) a[i] = n + 1 - a[i];
    for (int i = 0; i <= n+1; i++) inv[a[i]] = i;
    /*
    cout << "a : ";
    for (int i = 0; i <= n+1; i++) cout << a[i] << " ";
    cout << endl;
    cout << "b : ";
    for (int i = 0; i <= n+1; i++) cout << inv[i] << " ";
    cout << endl;
    */
}

ll ratkaise(int n) {
    ll ans = 0;
    //cout << "summa: " << 0 << " " << summa(1, 1) << endl;
    for (int i = 1; i <= n; i++) {
        if (inv[a[i]-1] < inv[a[i]] && inv[a[i]] < inv[a[i]+1]) { // 7 8 9
            muutavali(inv[a[i]-1]+1, inv[a[i]]-1, 1);
        }
        else if (inv[a[i]-1] < inv[a[i]+1] && inv[a[i]+1] < inv[a[i]]) { // 7 9 8
            //muutavali(1,inv[a[i]]-1, 1);
            muutavali(1, inv[a[i]+1]-1, 1);
            muutavali(inv[a[i]+1]+1, inv[a[i]]-1, 1);
        }
        else if (inv[a[i]] < inv[a[i]+1] && inv[a[i]+1] < inv[a[i]-1]) { // 8 9 7
            muutavali(1,inv[a[i]]-1, 1);
        }
        else if (inv[a[i]] < inv[a[i]-1] && inv[a[i]-1] < inv[a[i]+1]) { // 8 7 9
            muutavali(1,inv[a[i]]-1, 1);
        }
        else if (inv[a[i]+1] < inv[a[i]-1] && inv[a[i]-1] < inv[a[i]]) { // 9 7 8
            muutavali(1,inv[a[i]+1]-1, 1);
            muutavali(inv[a[i]-1]+1, inv[a[i]]-1, 1);
        }
        else if (inv[a[i]+1] < inv[a[i]] && inv[a[i]] < inv[a[i]-1]) { // 9 8 7
            muutavali(1,inv[a[i]]-1, 1);
        }
        /*
        cout << "summa: " << a[i] << endl;
        for (int i = 1; i <= n; i++) {
            cout << summa(1,i) << " ";
        }
        cout << endl;
        */
    }
    //cout << endl;
    for (int i = 1; i <= n; i++) {
        //cout << "summa: " << i << " " << a[i] << endl;
        if (inv[a[i]-1] < inv[a[i]] && inv[a[i]] < inv[a[i]+1]) { // 7 8 9
            muutavali(inv[a[i]-1]+1, inv[a[i]]-1, -1);
        }
        else if (inv[a[i]-1] < inv[a[i]+1] && inv[a[i]+1] < inv[a[i]]) { // 7 9 8
            //muutavali(1,inv[a[i]]-1, 1);
            muutavali(1, inv[a[i]+1]-1, -1);
            muutavali(inv[a[i]+1]+1, inv[a[i]]-1, -1);
        }
        else if (inv[a[i]] < inv[a[i]+1] && inv[a[i]+1] < inv[a[i]-1]) { // 8 9 7
            muutavali(1,inv[a[i]]-1, -1);
        }
        else if (inv[a[i]] < inv[a[i]-1] && inv[a[i]-1] < inv[a[i]+1]) { // 8 7 9
            muutavali(1,inv[a[i]]-1, -1);
        }
        else if (inv[a[i]+1] < inv[a[i]-1] && inv[a[i]-1] < inv[a[i]]) { // 9 7 8
            muutavali(1,inv[a[i]+1]-1, -1);
            muutavali(inv[a[i]-1]+1, inv[a[i]]-1, -1);
        }
        else if (inv[a[i]+1] < inv[a[i]] && inv[a[i]] < inv[a[i]-1]) { // 9 8 7
            muutavali(1,inv[a[i]]-1, -1);
        }
        cntIso[a[i]] = summa(1, inv[a[i]+1]);
        cntPieni[a[i]] = summa(1,inv[a[i]-1]);
        /*
        for (int i = 1; i <= n; i++) {
            cout << summa(1,i) << " ";
        }
        cout << endl;
        */
    }
    for (int i = 1; i <= n; i++) {
        //cout << i << " " << ans << endl;
        if (inv[a[i]] < inv[a[i]-1] && inv[a[i]-1] < inv[a[i]+1]) {
            ans += cntIso[a[i]-1] - cntPieni[a[i]+1];
            /*
            cout << "here" << endl;
            cout << cntIso[a[i]-1] << " " << a[i]-1 << endl;
            cout << cntPieni[a[i]+1] << " " << a[i] + 1 << endl;
            cout << endl;
            */
        }
        if (inv[a[i]+1] < inv[a[i]] && inv[a[i]] < inv[a[i]-1]) {
            ans += cntIso[a[i]-1];
        }
    }
    return ans;
}

int main() {
    int n;
    cin >> n;
    for (int i = 1; i <= n; i++) cin >> a[i];
    if (identity(n)) {
        cout << 2 << " " << n-1 << "\n";
        return 0;
    }
    int startval = solve(n);
    a[n+1] = n+1;
    for (int i = 0; i <= n+1; i++) inv[a[i]] = i;
    for (int i = 1; i <= n; i++) {
        if (inv[i-1] < inv[i+1] && inv[i+1] < inv[i]) {
            muutavali(inv[i-1]+1, inv[i+1]-1, 1);
        }
        if (inv[i+1] < inv[i] && inv[i] < inv[i-1]) {
            muutavali(1,inv[i+1]-1, 1);
        }
    }
    for (int i = 1; i <= n; i++) {
        if (inv[a[i]-1] < inv[a[i]+1] && inv[a[i]+1] < inv[a[i]]) { // 7 9 8
            muutavali(inv[a[i]-1]+1, inv[a[i]+1]-1, -1);
        }
        if (inv[a[i]+1] < inv[a[i]] && inv[a[i]] < inv[a[i]-1]) { // 9 8 7
            muutavali(1,inv[a[i]+1]-1, -1);
        }
        cntIso[a[i]] = summa(1, inv[a[i]+1]);
        cntPieni[a[i]] = summa(1,inv[a[i]-1]);
    }
    ll ans = 0;
    for (int i = 1; i <= n; i++) {
        if (inv[a[i]] < inv[a[i]-1] && inv[a[i]-1] < inv[a[i]+1]) {
            ans += cntIso[a[i]-1] - cntPieni[a[i]+1];
        }
        if (inv[a[i]+1] < inv[a[i]] && inv[a[i]] < inv[a[i]-1]) {
            ans += cntIso[a[i]-1];
        }
    }
    /*
    for (int i = 1; i <= n; i++) {
        cout << i << " " << cntIso[i] << " " << cntPieni[i] << endl;
    }
    */
    if (ans > 0) {
        cout << startval - 2 << " " << ans << "\n";
        return 0;
    }
    /*
    for (int i = 1; i <= n; i++) {
        cntIso[i] = 0;
        cntPieni[i] = 0;
    }
    */
    //for (int i = 0; i < 2*N; i++) p[i] = 0;
    for (int i = 1; i < n; i++) {
        if (inv[i+1] < inv[i] && (inv[i+2] < inv[i+1] || inv[i+2] > inv[i]) && (inv[i-1] < inv[i+1] || inv[i-1] > inv[i])) ans++;
    }
    //cout << ans << endl;
    ans += ratkaise(n);
    muunna(n);
    //for (int i = 0; i <= n+1; i++) cout << a[i] << " ";
    //cout << endl;
    //cout << ans << endl;
    ans += ratkaise(n);
    muunna(n);
    for (int i = 1; i < n; i++) {
        if (inv[i] < inv[i+1] && (inv[i-1] > inv[i] && inv[i-1] < inv[i+1]) && (inv[i+2] > inv[i] && inv[i+2] < inv[i+1])) ans--;
    }
    
    if (ans > 0) {
        cout << startval - 1 << " " << ans << "\n";
        return 0;
    }

    ans = (ll)n*(n-1)/2;
    //cout << ans << endl;
    for (int i = 1; i < n; i++) {
        if (inv[i] < inv[i+1]) {
            ans -= n - (inv[i+1] - inv[i]);
        } else {
            ans += n - (inv[i] - inv[i+1]);
        }
    }
    
    for (int i = 0; i <= n+1; i++) apu[i] = a[n+1-i];
    for (int i = 0; i <= n+1; i++) a[i] = apu[i];
    for (int i = 0; i <= n+1; i++) inv[a[i]] = i;
    
    ll ans2 = 0;
    for (int i = 1; i <= n; i++) {
        if (inv[i-1] < inv[i+1] && inv[i+1] < inv[i]) {
            muutavali(inv[i-1]+1, inv[i+1]-1, 1);
        }
        if (inv[i+1] < inv[i] && inv[i] < inv[i-1]) {
            muutavali(1,inv[i+1]-1, 1);
        }
    }
    for (int i = 1; i <= n; i++) {
        if (inv[a[i]-1] < inv[a[i]+1] && inv[a[i]+1] < inv[a[i]]) { // 7 9 8
            muutavali(inv[a[i]-1]+1, inv[a[i]+1]-1, -1);
        }
        if (inv[a[i]+1] < inv[a[i]] && inv[a[i]] < inv[a[i]-1]) { // 9 8 7
            muutavali(1,inv[a[i]+1]-1, -1);
        }
        cntIso[a[i]] = summa(1, inv[a[i]+1]);
        cntPieni[a[i]] = summa(1,inv[a[i]-1]);
    }
    for (int i = 1; i <= n; i++) {
        if (inv[a[i]] < inv[a[i]-1] && inv[a[i]-1] < inv[a[i]+1]) {
            ans2 += cntIso[a[i]-1] - cntPieni[a[i]+1];
        }
        if (inv[a[i]+1] < inv[a[i]] && inv[a[i]] < inv[a[i]-1]) {
            ans2 += cntIso[a[i]-1];
        }
    }
    cout << startval << " " << ans+ans2 << "\n";
}






 

Test details

Test 1

Group: 1, 2, 3

Verdict: ACCEPTED

input
100
1 2 3 4 5 6 7 8 9 10 11 12 13 ...

correct output
2 99

user output
2 99

Test 2

Group: 1, 2, 3

Verdict: ACCEPTED

input
100
100 99 98 97 96 95 94 93 92 91...

correct output
98 4851

user output
98 4851

Test 3

Group: 1, 2, 3

Verdict: ACCEPTED

input
100
1 2 88 4 5 6 7 8 9 10 11 12 13...

correct output
16 5

user output
16 5

Test 4

Group: 1, 2, 3

Verdict: ACCEPTED

input
100
51 48 74 70 45 71 24 88 55 99 ...

correct output
49 131

user output
49 131

Test 5

Group: 1, 2, 3

Verdict: ACCEPTED

input
100
45 67 29 62 70 77 41 74 52 95 ...

correct output
52 268

user output
52 268

Test 6

Group: 1, 2, 3

Verdict: ACCEPTED

input
100
47 98 2 75 6 21 84 8 4 89 27 9...

correct output
48 149

user output
48 149

Test 7

Group: 1, 2, 3

Verdict: ACCEPTED

input
100
73 68 17 94 71 63 61 13 58 10 ...

correct output
47 116

user output
47 116

Test 8

Group: 1, 2, 3

Verdict: ACCEPTED

input
100
17 16 45 94 6 1 36 81 31 13 51...

correct output
45 95

user output
45 95

Test 9

Group: 2, 3

Verdict: ACCEPTED

input
5000
1 2 3 4 5 6 7 8 9 10 11 12 13 ...

correct output
2 4999

user output
2 4999

Test 10

Group: 2, 3

Verdict: ACCEPTED

input
5000
5000 4999 4998 4997 4996 4995 ...

correct output
4998 12492501

user output
4998 12492501

Test 11

Group: 2, 3

Verdict: ACCEPTED

input
5000
1 2 3 4 5 6 7 8 9 10 11 12 13 ...

correct output
19 10

user output
19 10

Test 12

Group: 2, 3

Verdict: ACCEPTED

input
5000
1 2 3 4 5 6 264 8 9 10 11 12 1...

correct output
190 96

user output
190 96

Test 13

Group: 2, 3

Verdict: ACCEPTED

input
5000
1 2 3 4 5 6 7 8 9 2400 11 12 1...

correct output
1378 27938

user output
1378 27938

Test 14

Group: 2, 3

Verdict: ACCEPTED

input
5000
4012 2 4820 4208 1868 1728 362...

correct output
2511 436307

user output
2511 436307

Test 15

Group: 2, 3

Verdict: ACCEPTED

input
5000
3877 3972 1112 3669 1959 4640 ...

correct output
2497 417065

user output
2497 417065

Test 16

Group: 2, 3

Verdict: ACCEPTED

input
5000
2774 998 4525 2884 487 1995 41...

correct output
2518 426448

user output
2518 426448

Test 17

Group: 3

Verdict: ACCEPTED

input
200000
1 2 3 4 5 6 7 8 9 10 11 12 13 ...

correct output
2 199999

user output
2 199999

Test 18

Group: 3

Verdict: ACCEPTED

input
200000
200000 199999 199998 199997 19...

correct output
199998 19999700001

user output
199998 19999700001

Test 19

Group: 3

Verdict: ACCEPTED

input
200000
1 2 3 4 5 6 7 8 9 10 11 12 13 ...

correct output
19 10

user output
19 10

Test 20

Group: 3

Verdict: ACCEPTED

input
200000
1 2 3 4 5 6 7 8 9 10 11 12 13 ...

correct output
199 100

user output
199 100

Test 21

Group: 3

Verdict: ACCEPTED

input
200000
1 2 3 4 5 6 7 8 9 10 11 12 13 ...

correct output
1979 1030

user output
1979 1030

Test 22

Group: 3

Verdict: ACCEPTED

input
200000
1 2 184153 4 5 6 7 8 164545 10...

correct output
18081 477187

user output
18081 477187

Test 23

Group: 3

Verdict: ACCEPTED

input
200000
151013 68675 119105 58292 3335...

correct output
86328 318722426

user output
86328 318722426

Test 24

Group: 3

Verdict: ACCEPTED

input
200000
11562 33356 106752 170825 2723...

correct output
99873 663048119

user output
99873 663048119