B. Apple Tree violence + Math

Http://codeforces.com/problemset/problem/348/B

Notice that if the value of the vertex is determined, then the number of its points is determined, so the value of the vertex can be violently enumerated.

The number of vertices is separated from the LCM, LCM is, for example, 1 has three sub-nodes, then 1 of the value is at least a multiple of 3, or not divisible.

Similarly, 1 have three sons 2, 3, 4, if 3 have three sons, then 1 will be at least a multiple of 9, because the need to divide to 3 is at least 3.

So the LCM of the whole tree is calculated, the leaf node LCM is 1, the other LCM = LCM (All child nodes) * Son[cur]

After this, you can force the enumeration of the value of vertex 1, each enumeration is DFS once, a little violent 1700ms, learning to be solved first.

#include <cstdio>#include<cstdlib>#include<cstring>#include<cmath>#include<algorithm>#include<assert.h>#defineIOS Ios::sync_with_stdio (False)using namespacestd;#defineINF (0X3F3F3F3F)typedefLong Long intLL; #include<iostream>#include<sstream>#include<vector>#include<Set>#include<map>#include<queue>#include<string>Const intMAXN = 1e5 + -;intA[MAXN]; LL sum;structNode {intu, V, tonext;} E[MAXN*2];intFIRST[MAXN], num;voidAddedge (intUintv) {++num; E[NUM].U= u, e[num].v = V, E[num].tonext =First[u]; First[u]=num;}intVIS[MAXN], DFN =1;intSON[MAXN];voidFindson (intcur) {     for(inti = first[cur]; I i =E[i].tonext) {        intv =e[i].v; if(Vis[v] = = DFN)Continue; VIS[V]=DFN; Son[cur]++;    Findson (v); }}ll ans=1e18l, Tans; LL LCM; ll LCM (ll A, ll b) {returnA/__GCD (A, b) *b;}BOOLFlag;voidDfsintcur, LL val) {    if(flag)return; if(Son[cur] = =0) {        if(Val >A[cur]) {Flag=true; return; } Tans+ = A[cur]-Val; return; }     for(inti = first[cur]; I i =E[i].tonext) {        intv =e[i].v; if(Vis[v] = = DFN)Continue; VIS[V]=DFN; if(val% son[cur]! =0) {flag=true; return; } dfs (V, Val/Son[cur]); }}ll Calc (intcur) {    if(Son[cur] = =0)return 1; LL THISLCM=1;  for(inti = first[cur]; I i =E[i].tonext) {        intv =e[i].v; if(Vis[v] = = DFN)Continue; VIS[V]=DFN; THISLCM=LCM (THISLCM, Calc (v)); }    if(THISLCM > Sum/Son[cur]) {printf ("%i64d\n", sum); Exit (0); }    returnSon[cur] *THISLCM;}voidWork () {intN; scanf ("%d", &N); LCM=1;  for(inti =1; I <= N; ++i) {scanf ("%d", &A[i]); Sum+=A[i]; }     for(inti =1; I <= N-1; ++i) {intu, v; scanf ("%d%d", &u, &v);        Addedge (U, v);    Addedge (V, u); } vis[1] =DFN; Findson (1); ++DFN; vis[1] =DFN; LCM= Calc (1);//cout << LCM << Endl;Ans =sum; Sum/=LCM; Sum*=LCM;  for(LL i = sum; I >= LCM; I-=LCM) {++DFN, tans =0; Flag=false;//DFS (1);vis[1] =DFN; DFS (1, i); if(flag)Continue; printf ("%i64d\n", ans-i); return; } printf ("%i64d\n", ans);}intMain () {#ifdef local freopen ("Data.txt","R", stdin);//freopen ("Data.txt", "w", stdout);#endifWork (); return 0;}

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B. Apple Tree violence + Math