Hdu1232 smooth engineering and query set

This question is very similar to HDU 1213 how many tables and query sets.

Idea: Suppose we still need to build n-1 routes, and each merge will be reduced by 1.

Reference code:

#include<stdio.h>int fa[1000];int find(int u){    return fa[u]==u?u:fa[u]=find(fa[u]);}int main(){    int i,n,m,u,v,x,y;    scanf("%d%d",&n,&m);    while (n)    {        for (i=1;i<=n;i++) fa[i]=i;        for (i=1;i<=m;i++)        {            scanf("%d%d",&u,&v);            x=find(u);y=find(v);            if (x!=y)            {                fa[x]=y;                n--;            }        }        n--;        printf("%d\n",n);       scanf("%d%d",&n,&m);    }   return 0;}

Optimization: first store the number of M groups in arrays, and then only store the root nodes of these nodes.

Initial Value Fa [U [I] = U [I]; Fa [V [I] = V [I];

Reference code:

#include<stdio.h>int fa[1000],u[1000],v[1000];int find(int u){    return fa[u]==u?u:fa[u]=find(fa[u]);}int main(){    int i,n,m,x,y;    scanf("%d%d",&n,&m);    while (n)    {        for (i=1;i<=m;i++)        {            scanf("%d%d",&u[i],&v[i]);            fa[u[i]]=u[i];            fa[v[i]]=v[i];        }        for (i=1;i<=m;i++)        {          x=find(u[i]);y=find(v[i]);            if (x!=y)            {                fa[x]=y;                n--;            }        }        n--;        printf("%d\n",n);       scanf("%d%d",&n,&m);    }   return 0;}