Submission #1558508

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Source Code Expand

#include <iostream>
#include <cstring>
#include <string>
#include <vector>
#include <cmath>
#include <map>
#include <queue>
#include <set>
#include <algorithm>
#include <iomanip>
#include <cassert>

using namespace std;

const int mod = 1000000007;

int p[100500];

int main(){
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    int n, a;
    cin >> n;
    int ans = 0;
    for (int i = 1; i <= n; i++){
        cin >> p[i];
    }
    for (int i = 1; i < n; i++)
        if (p[i] == i){
            ans++;
            swap(p[i], p[i + 1]);
        }
    if (p[n] == n){
        ans++;
        swap(p[n - 1], p[n]);
    }
    cout << ans;    
    return 0;
}

Submission Info

Judge Result