#include <cstdio> #include <cstring> #include <iostream> #include <algorithm> #include <vector> using namespace std; typedef long long ll; const int MAX = 100010; vector<int> G[MAX]; vector<int> SH[MAX]; ll GD[MAX]; int QE[MAX]; int W[MAX]; ll T[MAX]; ll DS[MAX]; int main() { int n,q; scanf("%d%d",&n,&q); for(int i=0;i<n;++i) scanf("%lld",&T[i]); int a,b; ll c; int wg=0; for(int i=0;i<n-1;++i) { scanf("%d%d",&a,&b); scanf("%lld",&c); GD[wg]=c; G[a-1].push_back(b-1); G[b-1].push_back(a-1); SH[a-1].push_back(wg); SH[b-1].push_back(wg); ++wg; } int v; int r; ll d; int ac=0; for(int j=1;j<=q;++j) { scanf("%d",&r); if (r==1) { scanf("%d",&v); scanf("%lld",&d); T[v-1]=d; } else { scanf("%d%d",&a,&b); scanf("%lld",&d); for(int i=0;i<G[a-1].size();++i) { if (G[a-1][i]==b-1) { GD[SH[a-1][i]]=d; break; } } } W[ac]=j; QE[0]=ac; int w1=0,w2=1; ll cn=-1000000000000000000L; DS[ac]=0L; while(w1<w2) { int cv=QE[w1++]; for(int i=0;i<G[cv].size();++i) { int ng=G[cv][i]; ll ds=GD[SH[cv][i]]; if (W[ng]==j) continue; W[ng]=j; QE[w2++]=ng; DS[ng]=DS[cv]+ds; if (T[ng]-DS[ng]>cn||(T[ng]-DS[ng]==cn&&ng<ac)) { cn=T[ng]-DS[ng]; ac=ng; } } } printf("%d ", ac+1); } return 0; }
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 | #include <cstdio> #include <cstring> #include <iostream> #include <algorithm> #include <vector> using namespace std; typedef long long ll; const int MAX = 100010; vector<int> G[MAX]; vector<int> SH[MAX]; ll GD[MAX]; int QE[MAX]; int W[MAX]; ll T[MAX]; ll DS[MAX]; int main() { int n,q; scanf("%d%d",&n,&q); for(int i=0;i<n;++i) scanf("%lld",&T[i]); int a,b; ll c; int wg=0; for(int i=0;i<n-1;++i) { scanf("%d%d",&a,&b); scanf("%lld",&c); GD[wg]=c; G[a-1].push_back(b-1); G[b-1].push_back(a-1); SH[a-1].push_back(wg); SH[b-1].push_back(wg); ++wg; } int v; int r; ll d; int ac=0; for(int j=1;j<=q;++j) { scanf("%d",&r); if (r==1) { scanf("%d",&v); scanf("%lld",&d); T[v-1]=d; } else { scanf("%d%d",&a,&b); scanf("%lld",&d); for(int i=0;i<G[a-1].size();++i) { if (G[a-1][i]==b-1) { GD[SH[a-1][i]]=d; break; } } } W[ac]=j; QE[0]=ac; int w1=0,w2=1; ll cn=-1000000000000000000L; DS[ac]=0L; while(w1<w2) { int cv=QE[w1++]; for(int i=0;i<G[cv].size();++i) { int ng=G[cv][i]; ll ds=GD[SH[cv][i]]; if (W[ng]==j) continue; W[ng]=j; QE[w2++]=ng; DS[ng]=DS[cv]+ds; if (T[ng]-DS[ng]>cn||(T[ng]-DS[ng]==cn&&ng<ac)) { cn=T[ng]-DS[ng]; ac=ng; } } } printf("%d ", ac+1); } return 0; } |