#include <bits/stdc++.h> using namespace std; #define int long long #define ii pair<int,int> #define iii tuple<int,int,int> #define fi first #define se second #define endl '\n' #define pub push_back #define pob pop_back #define puf push_front #define pof pop_front #define lb lower_bound #define ub upper_bound #define rep(x,start,end) for(int x=(start)-((start)>(end));x!=(end)-((start)>(end));((start)<(end)?x++:x--)) #define all(x) (x).begin(),(x).end() #define sz(x) (int)(x).size() mt19937 rng(chrono::system_clock::now().time_since_epoch().count()); const int MX=1'000'000'000; const int K=100'000; int n,m; int arr[105]; vector<ii> al[205]; vector<ii> alr[205]; bool vis[105][K+5]; int best[105][K+5]; void dfs(int i,int j){ if (j>min(K,arr[i])) return; if (vis[i][j]) return; vis[i][j]=true; for (auto [it,w]:al[i]){ dfs(it,j*w); } } int mx[105][MX/K+5]; signed main(){ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin.exceptions(ios::badbit | ios::failbit); int TC; cin>>TC; while (TC--){ cin>>n>>m; rep(x,1,n+1) cin>>arr[x]; rep(x,1,n+1) al[x].clear(); rep(x,1,n+1) alr[x].clear(); rep(x,1,n+1){ memset(vis[x],false,sizeof(vis[x])); memset(best[x],-1,sizeof(best[x])); memset(mx[x],0,sizeof(mx[x])); } rep(x,0,m){ int a,b,c; cin>>a>>b>>c; al[a].pub({b,c}); alr[b].pub({a,c}); } dfs(1,1); rep(x,1,n+1){ rep(y,0,K+1){ if (vis[x][y]) best[x][y]=y; else if (y) best[x][y]=best[x][y-1]; } } priority_queue<iii,vector<iii> > pq; mx[n][1]=arr[n]; pq.push({mx[n][1],n,1}); while (!pq.empty()){ int w,a,b; tie(w,a,b)=pq.top(); pq.pop(); if (w!=mx[a][b]) continue; for (auto [it,b2]:alr[a]) if (b*b2<=MX/K){ int mx2=min(w/b2,arr[it]); if (mx[it][b*b2]<mx2){ mx[it][b*b2]=mx2; pq.push({mx2,it,b*b2}); } } } int ans=-1; if (n==1) ans=1; rep(x,1,n+1) rep(y,1,MX/K+1) for (auto [it,w]:alr[x]){ int oth=min(mx[x][y]/w,K); if (best[it][oth]!=-1) ans=max(ans,best[it][oth]*w*y); } cout<<ans<<endl; } }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 | #include <bits/stdc++.h> using namespace std; #define int long long #define ii pair<int,int> #define iii tuple<int,int,int> #define fi first #define se second #define endl '\n' #define pub push_back #define pob pop_back #define puf push_front #define pof pop_front #define lb lower_bound #define ub upper_bound #define rep(x,start,end) for(int x=(start)-((start)>(end));x!=(end)-((start)>(end));((start)<(end)?x++:x--)) #define all(x) (x).begin(),(x).end() #define sz(x) (int)(x).size() mt19937 rng(chrono::system_clock::now().time_since_epoch().count()); const int MX=1'000'000'000; const int K=100'000; int n,m; int arr[105]; vector<ii> al[205]; vector<ii> alr[205]; bool vis[105][K+5]; int best[105][K+5]; void dfs(int i,int j){ if (j>min(K,arr[i])) return; if (vis[i][j]) return; vis[i][j]=true; for (auto [it,w]:al[i]){ dfs(it,j*w); } } int mx[105][MX/K+5]; signed main(){ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin.exceptions(ios::badbit | ios::failbit); int TC; cin>>TC; while (TC--){ cin>>n>>m; rep(x,1,n+1) cin>>arr[x]; rep(x,1,n+1) al[x].clear(); rep(x,1,n+1) alr[x].clear(); rep(x,1,n+1){ memset(vis[x],false,sizeof(vis[x])); memset(best[x],-1,sizeof(best[x])); memset(mx[x],0,sizeof(mx[x])); } rep(x,0,m){ int a,b,c; cin>>a>>b>>c; al[a].pub({b,c}); alr[b].pub({a,c}); } dfs(1,1); rep(x,1,n+1){ rep(y,0,K+1){ if (vis[x][y]) best[x][y]=y; else if (y) best[x][y]=best[x][y-1]; } } priority_queue<iii,vector<iii> > pq; mx[n][1]=arr[n]; pq.push({mx[n][1],n,1}); while (!pq.empty()){ int w,a,b; tie(w,a,b)=pq.top(); pq.pop(); if (w!=mx[a][b]) continue; for (auto [it,b2]:alr[a]) if (b*b2<=MX/K){ int mx2=min(w/b2,arr[it]); if (mx[it][b*b2]<mx2){ mx[it][b*b2]=mx2; pq.push({mx2,it,b*b2}); } } } int ans=-1; if (n==1) ans=1; rep(x,1,n+1) rep(y,1,MX/K+1) for (auto [it,w]:alr[x]){ int oth=min(mx[x][y]/w,K); if (best[it][oth]!=-1) ans=max(ans,best[it][oth]*w*y); } cout<<ans<<endl; } } |