#include <iostream>

using namespace std;
const int N = 1000010;
int a[N];
int n, m;
int d[N], s[N], t[N];
int b[N];

bool check(int mid)
{
    for (int i = 1; i <= n; i++) b[i] = a[i];

    for (int i = n; i >= 1; i--) b[i] -= b[i - 1];

    for (int i = 1; i <= mid; i++)
    {
        b[s[i]] -= d[i], b[t[i] + 1] += d[i];
    }

    int res = 0;
    for (int i = 1; i <= n; i++)
    {
        res += b[i];
        if (res < 0) return true;
    }

    return false;
}

int main()
{
    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%d", d + i, s + i, t + i);

    int l = 0, r = m;
    while (l < r)
    {
        int mid = l + r >> 1;
        if (check(mid)) r = mid;
        else l = mid + 1;
    }

    if (l == m) cout << 0;
    else cout << -1 << endl << r << endl;

    return 0;
}