#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <vector>

using namespace std;

const int MAXN = 100000 + 100;
const int MAXM = 1000 + 100;
const int INF = 0x3f3f3f3f;

int n, m, M;
int h[MAXN], d[MAXN], c[MAXN], a[MAXN];
int s[MAXN];
int f[MAXM][MAXM];
long long ans = 0;

void init()
{
    ans = 0, M = 0;
    memset(f, 63, sizeof(f));
}

void solve()
{
    f[0][0] = 0;
    for(int i = 1; i <= m; i++)
        for(int j = 0; j <= M; j++)
        {
            f[i][j] = f[i - 1][j];
            if(s[i] > 0)
                f[i][j] = min(f[i][j], (j - s[i] >= 0 ? f[i][j - s[i]] : 0) + c[i]);
        }
}

void work()
{
    init();
    for(int i = 1; i <= n; i++)
        cin >> h[i] >> d[i];
    for(int i = 1; i <= m; i++)
        cin >> c[i] >> a[i];
    for(int def = 0; def <= 10; def++)
    {
        for(int i = 1; i <= m; i++)
            s[i] = a[i] - def;
        M = 0;
        for(int i = 1; i <= n; i++)
            if(d[i] == def)
                M = max(M, h[i]);
        solve();
        if(f[m][M] >= INF)
        {
            cout << -1 << endl;
            return ;    
        }
        for(int i = 1; i <= n; i++)
            if(d[i] == def)
                ans += f[m][h[i]];
    }
    cout << ans << endl;
}

int main()
{
    ios::sync_with_stdio(false);
//    freopen("1.in", "r", stdin);
//    freopen("1.out", "w", stdout);

    while(cin >> n >> m)
        work();
    
    
    return 0;
}