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

int N, M;

int main() {
    cin >> N >> M;
    vector<int> S(N);
    for (size_t i = 0; i < N; i++)
    {
        cin >> S[i];
    }
    int a, b;
    for (size_t i = 0; i < M; i++)
    {
        cin >> a >> b;
        a--; b--;
        sort(S.begin() + a, S.begin() + b + 1);
    }
    int counter = 0;
    for (size_t i = 0; i < S.size(); i++)
    {
        if (S[i] == i + 1) counter++;
    }
    cout << counter;
}