#include <bits/stdc++.h>
using namespace std;
const int maxn = 255;
int a[maxn],s[maxn],d[maxn],n,m;
bool f[maxn][maxn];
int main() {
    freopen("snowboots_silver_18feb.in","r",stdin);
    freopen("snowboots_silver_18feb.out","w",stdout);
    scanf("%d%d",&n,&m);
    for(int i = 1;i <= n;++ i)scanf("%d",&a[i]);
    for(int i = 1;i <= m;++ i) {
        scanf("%d%d",&s[i],&d[i]);
    }
    f[1][0] = true;
    for(int i = 1;i <= m;++ i)f[1][i] = true;
    for(int i = 2;i <= n;++ i) {
        for(int j = 1;j <= m;++ j) {
            f[i][j] |= f[i][j - 1];
            if(a[i] > s[j])continue ;
            for(int k = 1;k <= d[j];++ k) {
                if(i - k <= 0)break ;
                if(a[i - k] > s[j])continue ;
                f[i][j] |= f[i - k][j];
            }
        }
    }
    int ans = 0;
    for(int j = 1;j <= m;++ j) {
        if(f[n][j]) {
            ans = j - 1;
            break ;
        }
    }
    printf("%d",ans);
    fclose(stdin);
    fclose(stdout);
    return 0;
}