#include<bits/stdc++.h>
using namespace std;
const int N=260;
int n,b;
int f[N],s[N],d[N];
int dp[N];
int main()
{
    freopen("snowboots_silver_18feb.in","r",stdin);
    freopen("snowboots_silver_18feb.out","w",stdout);
    memset(dp,0x3f,sizeof(dp));
    dp[1]=0;
    scanf("%d%d",&n,&b);
    for(int i=1;i<=n;i++)
        scanf("%d",&f[i]);
    for(int i=1;i<=b;i++)
        scanf("%d%d",&s[i],&d[i]);
    for(int i=1;i<n;i++)
        for(int j=dp[i]+1;j<=b;j++)
        {
            if(s[j]<f[i]) continue;
            for(int k=i+1;k<=i+d[j];k++)
                if(s[j]>=f[k]) dp[k]=min(dp[k],j-1);
        }
    printf("%d",dp[n]);
    return 0;
}