1 #include<iostream>
2 #include<string>
3 #include<queue>
4 #include<stack>
5 #include<vector>
6 #include<map>
7 #include<cstdio>
8 #include<cstdlib>
9 #include<algorithm>
10 #include<set>
11 #include<list>
12 #include<iomanip>
13 #include<cstring>
14 #include<cmath>
15 #include<limits>
16 using namespace std;
17
18 #define au auto
19 #define debug(i) cout<<"<debug> "<<i<<"<\debug>"<<endl
20 #define mfor(i,a,b) for(register int i=(a);i<=(b);i++)
21 #define mrep(i,a,b) for(register int i=(a);i>=(b);i--)
22 #define LLL __int128
23 #define Re register
24 #define il inline
25 #define mem(a,b) memset(a,(b),sizeof(a))
26 typedef pair<int, int> intpair;
27 typedef long long int LL;
28 const int INF = 0x3f3f3f3f;
29 const long long int INFLL = 0x3f3f3f3f3f3f3f3f;
30
31 const int maxn = 5000010;
32 int a[maxn];
33 int n, m;
34
35 #define lc(x) x<<1
36 #define rc(x) x<<1|1
37
38 il int min(int a, int b)
39 {
40 return a > b ? b : a;
41 }
42
43 struct tree
44 {
45 int a;
46 int l, r;
47 int tag;
48 tree()
49 {
50 tag = 0;
51 l = 0;
52 r = 0;
53 a = 0;
54 }
55 }node[maxn];
56
57 void build(int x, int l, int r)
58 {
59 node[x].l = l;
60 node[x].r = r;
61 if (l == r)
62 {
63 node[x].a = a[l];
64 return;
65 }
66 int mid = (l + r) >> 1;
67 build(lc(x), l, mid);
68 build(rc(x), mid + 1, r);
69 node[x].a = min(node[lc(x)].a, node[rc(x)].a);
70 }
71
72 inline void push_down(int x)
73 {
74 node[lc(x)].tag += node[x].tag;
75 node[lc(x)].a += node[x].tag;
76 node[rc(x)].a += node[x].tag;
77 node[rc(x)].tag += node[x].tag;
78 node[x].tag = 0;
79 }
80
81 inline void update(int left, int right, int x, int k)
82 {
83 if (left <= node[x].l && node[x].r <= right)
84 {
85 node[x].a += k;
86 node[x].tag += k;
87 return;
88 }
89 push_down(x);
90 int mid = (node[x].l + node[x].r) >> 1;
91 if (left <= mid) update(left, right, lc(x), k);
92 if (right > mid) update(left, right, rc(x), k);
93 node[x].a = min(node[lc(x)].a, node[rc(x)].a);
94 }
95
96 int query(int left, int right, int x)
97 {
98 int res = INF;
99 if (left <= node[x].l && node[x].r <= right) return node[x].a;
100 int mid = (node[x].l + node[x].r) >> 1;
101 if (left <= mid) res = min(res, query(left, right, lc(x)));
102 if (right > mid) res = min(res, query(left, right, rc(x)));
103 return res;
104 }
105
106 int main()
107 {
108 ios::sync_with_stdio(0);
109 cin.tie(0);
110 cin >> n >> m;
111 mfor(i, 1, n)
112 {
113 cin >> a[i];
114 }
115 build(1, 1, n);
116 mfor(i, 1, m)
117 {
118 int a, b, c;
119 cin >> a >> b >> c;
120 update(b, c, 1, -a);
121 if (query(1, n, 1) < 0)
122 {
123 cout << -1 << endl;
124 cout << i;
125 return 0;
126 }
127 }
128 cout << 0;
129 }
