#include<bits/stdc++.h>
using namespace std;
int n,b,f[255],dp[255][255],d[255],s[255];
int main(){
    freopen("snowboots_silver_18feb.in","r",stdin);
    freopen("snowboots_silver_18feb.out","w",stdout);
    cin>>n>>b;
    dp[1][1]=1;
    for(int i=1;i<=n;i++) cin>>f[i];
    for(int i=1;i<=b;i++) cin>>s[i]>>d[i];
    for(int i=1;i<=n;i++) 
        for(int j=1;j<=b;j++)
            if(dp[i][j])
                for(int k=j;k<=b;k++)
                    if(f[i]<=s[k])
                        for(int h=i+1;h<=min(n,i+d[k]);h++)
                            if(f[h]<=s[k])
                                dp[h][k]=1;
    for(int i=1;i<=b;i++){
        if(dp[n][i]){
            cout<<i-1;
            return 0;
        }
    }
    return 0;
}