HDU 5876 Sparse Graph

#pragma comment(linker, "/STACK:1024000000,1024000000")
#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<vector>
#include<map>
#include<set>
#include<queue>
#include<stack>
#include<iostream>
using namespace std;
typedef long long LL;
const double pi=acos(-1.0),eps=1e-6;
void File()
{
freopen("D:\\in.txt","r",stdin);
freopen("D:\\out.txt","w",stdout);
}
template <class T>
inline void read(T &x)
{
char c=getchar(); x=0;
while(!isdigit(c)) c=getchar();
while(isdigit(c)) {x=x*10+c-'0'; c=getchar();}
}

const int maxn=200010;
int T,n,m,d[maxn],sz,h[maxn],s;
struct Edge{int u,v,nx;}e[maxn];

void add(int u,int v)
{
e[sz].u=u; e[sz].v=v;
e[sz].nx=h[u]; h[u]=sz++;
}

int main()
{
scanf("%d",&T);
while(T--)
{
scanf("%d%d",&n,&m);
memset(d,-1,sizeof d);
memset(h,-1,sizeof h); sz=0;
for(int i=1;i<=m;i++)
{
int u,v; scanf("%d%d",&u,&v);
add(u,v); add(v,u);
}
scanf("%d",&s); d[s]=0;

sz=1; int dis=0;
while(1)
{
int sum=0; dis++;
for(int i=1;i<=n;i++)
{
if(d[i]!=-1) continue;
int g=0;
for(int j=h[i];j!=-1;j=e[j].nx)
if(d[e[j].v]!=-1&&d[e[j].v]<dis) g++;
if(sz==g) continue;
d[i]=dis; sum++;
}
if(sum==0) break;
sz=sz+sum; if(sz==n) break;
}

sz=0;
for(int i=1;i<=n;i++)
{
if(i==s) continue;
sz++; printf("%d",d[i]);
if(sz<n-1) printf(" "); else printf("\n");
}
}
return 0;
}