Submission #1607324

---

Source Code Expand

#include <bits/stdc++.h>

using namespace std;

namespace {

    typedef double real;
    typedef long long ll;

    template<class T> ostream& operator<<(ostream& os, const vector<T>& vs) {
        if (vs.empty()) return os << "[]";
        auto i = vs.begin();
        os << "[" << *i;
        for (++i; i != vs.end(); ++i) os << " " << *i;
        return os << "]";
    }
    template<class T> istream& operator>>(istream& is, vector<T>& vs) {
        for (auto it = vs.begin(); it != vs.end(); it++) is >> *it;
        return is;
    }

    int N;
    vector<int> P;
    void input() {
        cin >> N;
        P.resize(N);
        cin >> P;
    }
    void solve() {
        int ans = 0;
        for (int i = 0; i < P.size(); i++) {
            auto p = P[i];
            if (p == i + 1) {
                ans++;
                swap(P[i], P[i + 1]);
            }
        }
        cout << ans << endl;
    }
}

int main() {
    input(); solve();
    return 0;
}

Submission Info

Judge Result