【链接】
bzoj1202
【解题报告】
并查集维护前缀和。
#include<cstdio>
#include<cstring>
using namespace std;
const int maxn=105;
int n,m,T,fa[maxn],w[maxn];
inline char nc()
{
static char buf[100000],*l,*r;
if (l==r) r=(l=buf)+fread(buf,1,100000,stdin);
if (l==r) return EOF; return *l++;
}
inline int Read()
{
int res=0,f=1; char ch=nc(),cc=ch;
while (ch<'0'||ch>'9') cc=ch,ch=nc();
if (cc=='-') f=-1;
while (ch>='0'&&ch<='9') res=res*10+ch-48,ch=nc();
return res*f;
}
int Getfa(int x)
{
if (x==fa[x]) return x;
int t=Getfa(fa[x]);
w[x]+=w[fa[x]]; fa[x]=t;
return fa[x];
}
void Work()
{
n=Read(); m=Read();
memset(w,0,sizeof(w));
for (int i=0; i<=n; i++) fa[i]=i;
for (int i=1; i<=m; i++)
{
int x=Read()-1,y=Read(),z=Read(),fx=Getfa(x),fy=Getfa(y);
printf("%d %d %d %d %d %d %d\n",x,y,z,fx,fy,w[x],w[y]);
if (fx!=fy) {w[fx]=w[y]-w[x]-z; fa[fx]=fy;}
else if (w[y]-w[x]!=z) {printf("false\n"); return;}
}
printf("true\n");
}
void Print()
{
for (int i=1; i<=n; i++) printf("%d ",w[i]);
}
int main()
{
freopen("1202.in","r",stdin);
freopen("1202.out","w",stdout);
T=Read();
while (T--) Work(),Print();
return 0;
}