题目链接:
http://acm.uestc.edu.cn/#/problem/show/1070
题意:
题解:
带权并查集
每次往上更新的时候，顺便把边权更新了就好
记住得路径压缩
代码:
1 #include <bits/stdc++.h> 2 using namespace std; 3 typedef long long ll; 4 #define MS(a) memset(a,0,sizeof(a)) 5 #define MP make_pair 6 #define PB push_back 7 const int INF = 0x3f3f3f3f; 8 const ll INFLL = 0x3f3f3f3f3f3f3f3fLL; 9 inline ll read(){ 10 ll x=0,f=1;char ch=getchar(); 11 while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();} 12 while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();} 13 return x*f; 14 } 15 ////////////////////////////////////////////////////////////////////////// 16 const int maxn = 1e5+10; 17 18 int fa[maxn]; 19 ll w[maxn]; 20 21 int find(int x){ 22 if(fa[x] == x) return x; 23 24 find(fa[x]); 25 w[x] += w[fa[x]]; 26 fa[x] = find(fa[x]); 27 return fa[x]; 28 } 29 30 void Union(int v,int u){ 31 int t1 = find(v), t2 = find(u); 32 if(t1 == t2) return ; 33 fa[v] = t2; 34 w[v] = abs(u-v) % 1000 + w[u]; 35 } 36 37 int main(){ 38 int n=read(); 39 for(int i=0; i<=n; i++){ 40 fa[i] = i; 41 w[i] = 0; 42 } 43 char op; 44 while(scanf(" %c",&op) && op!='O'){ 45 if(op=='I'){ 46 int v,u; scanf("%d%d",&v,&u); 47 Union(v,u); 48 }else{ 49 int x=read(); 50 find(x); 51 printf("%lld ",w[x]); 52 } 53 } 54 55 return 0; 56 }