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#include <cstdio>
#include <algorithm>
#include <vector>
#include <queue>
#include <cstring>
#define pe pair<int,int>
#define mp make_pair
#define fi first
#define se second
using namespace std;
const int MAX_N=50;
const int INF=100;
const int MAX_V=5010;
int n;
vector<pe> A[MAX_N];
vector<int> G[MAX_V];
int cap[MAX_V][MAX_V];
int flux[MAX_V][MAX_V];
int D;
void graf(int T) {
D=T*n+1;
for(int i=1;i<=n;i++) {
G[n*(T-1)+i].push_back(n*T+i);
G[n*T+i].push_back(n*(T-1)+i);
cap[n*(T-1)+i][n*T+i]=INF;
}
for(int i=1;i<=n;i++) {
for(auto it=A[i].begin(); it!=A[i].end(); it++) {
G[n*(T-1)+i].push_back(n*T + it->fi);
G[n*T + it->fi].push_back(n*(T-1)+i);
cap[n*(T-1)+i][n*T+ it->fi]=it->se;
}
}
}
bool viz[MAX_V];
int dad[MAX_V];
bool bfs() {
memset(viz,0,sizeof(viz));
memset(dad,0,sizeof(dad));
queue<int> Q;
Q.push(0);
viz[0]=true;
while(!Q.empty()) {
int nod=Q.front();
Q.pop();
if(nod==D) {
continue;
}
for(auto it=G[nod].begin(); it!=G[nod].end(); it++) {
if(!viz[*it]&&flux[nod][*it]<cap[nod][*it]) {
viz[*it]=true;
dad[*it]=nod;
Q.push(*it);
}
}
}
return viz[D];
}
int ans;
void flow() {
while(bfs()) {
for(auto it=G[D].begin(); it!=G[D].end(); it++) {
if(!viz[*it]||flux[*it][D]>=cap[*it][D]) {
continue;
}
dad[D]=*it;
int mflow=12;
for(int nod=D;nod;nod=dad[nod]) {
mflow=min(mflow,cap[dad[nod]][nod]-flux[dad[nod]][nod]);
}
ans+=mflow;
for(int nod=D;nod;nod=dad[nod]) {
flux[dad[nod]][nod]+=mflow;
flux[nod][dad[nod]]=mflow;
}
}
}
}
int main() {
freopen("algola.in","r",stdin);
freopen("algola.out","w",stdout);
int m;
int sum=0;
scanf("%d%d",&n,&m);
for(int i=1;i<=n;i++) {
int c;
scanf("%d",&c);
G[0].push_back(i);
G[i].push_back(0);
cap[0][i]=c;
sum+=c;
}
for(int i=1;i<=m;i++) {
int a,b,c;
scanf("%d%d%d",&a,&b,&c);
A[a].push_back(mp(b,c));
A[b].push_back(mp(a,c));
}
int t;
for(t=1;ans<sum;t++) {
graf(t);
flow();
}
printf("%d",t-1);
return 0;
}