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 pair<long long int, long long int> llpair;
28 typedef long long int LL;
29 const int INF = 0x3f3f3f3f;
30 const long long int INFLL = 0x3f3f3f3f3f3f3f3f;
31
32 int cnt;
33 int n, m;
34 const int maxn = 300010;
35 int v[maxn];
36
37 struct Edge
38 {
39 int u, nxt;
40 int w;
41 }e[maxn * 3];
42
43 int head[maxn * 3];
44
45 void add(int a, int b, int w)
46 {
47 e[++cnt].u = b;
48 e[cnt].nxt = head[a];
49 head[a] = cnt;
50 e[cnt].w = w;
51 }
52
53 int dis[maxn * 3];
54 bool vis[maxn * 3];
55 queue<int>q;
56
57 void spfa(int x)
58 {
59 mem(dis, -0x3f);
60 mem(vis, false);
61 dis[x] = 0;
62 q.push(x);
63 vis[x] = true;
64 while (!q.empty())
65 {
66 int t = q.front();
67 q.pop();
68 vis[t] = false;
69 for (Re int i = head[t]; i != -1; i = e[i].nxt)
70 {
71 int u = e[i].u;
72 int w = e[i].w;
73 if (dis[u] < dis[t] + w)
74 {
75 dis[u] = dis[t] + w;
76 if (!vis[u])
77 {
78 q.push(u);
79 vis[u] = true;
80 }
81 }
82 }
83 }
84 }
85
86 int main()
87 {
88 mem(head, -1);
89 cin >> n >> m;
90 mfor(i, 1, n) cin >> v[i];
91 mfor(i, 1, m)
92 {
93 int a, b, c;
94 cin >> b >> c >> a;
95 add(b, c, 0);
96 add(n + b, n + c, 0);
97 add((n << 1) + b, (n << 1) + c, 0);
98 add(b, n + c, -v[b]);
99 add(n + b, (n << 1) + c, v[b]);
100 if (a == 2)
101 {
102 add(c, b, 0);
103 add(n + c, n + b, 0);
104 add((n << 1) + c, (n << 1) + b, 0);
105 add(c, n + b, -v[c]);
106 add(n + c, (n << 1) + b, v[c]);
107 }
108 }
109 add(n, 3 * n + 1, 0);
110 add(n * 3, n * 3 + 1, 0);
111 spfa(1);
112 cout << dis[n * 3 + 1];
113 return 0;
114 }
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