#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

#define getrp() ({char*mmap();mmap(0l,1l<<25,1,2,0,0ll);})
#define rd() ({long _v=0,_c;while(_c=*rp++-48,_c>=0)_v=_v*10+_c;_v;})
#define wt(v) ({ulong _z=v;do*--wp=_z%10+48;while(_z/=10);})
#define wt1(v) ({char wbuf[64],*wp=wbuf+sizeof wbuf;wt(v);write(1,wp,wbuf+sizeof wbuf-wp);})
#define rep(v,e) for(long v=0;v<e;++v)

typedef unsigned long ulong;

ulong e0[200000],e1[200000];

void radix_sort_aux(ulong*a,ulong*b,long n,long last){
	int c[512];
	for(long i=0;i<512;++i){
		c[i]=0;
	}
	for(long i=0;i<n;++i){
		++c[a[i]&511];
	}
	int t=0;
	for(long i=0;i<512;++i){
		int u=c[i];
		c[i]=t;
		t+=u;
	}
	if(!last){
		for(long i=0;i<n;++i){
			b[c[a[i]&511]++]=a[i]>>9|a[i]<<55;
		}
	}else{
		for(long i=0;i<n;++i){
			b[c[a[i]&511]++]=a[i]>>46|a[i]<<18;
		}
	}
}

#define UFSIZE 100001
int ufbuf[UFSIZE];
void uf_init(){
	for(int i=0;i<UFSIZE;++i){
		ufbuf[i]=-1;
	}
}
static inline
int uf_root(int a){
	int b;
	int t=a;
	while(b=ufbuf[t],b>=0) t=b;
	while(b=ufbuf[a],b>=0) ufbuf[a]=t,a=b;
	return t;
}
static inline
void uf_unite(int a,int b){
	//a=uf_root(a);
	//b=uf_root(b);
	if(a!=b){
		if(ufbuf[a]<ufbuf[b]){
			ufbuf[a]+=ufbuf[b];
			ufbuf[b]=a;
		}else{
			ufbuf[b]+=ufbuf[a];
			ufbuf[a]=b;
		}
	}
}

int main(){
	char*rp=getrp();
	long n=rd();
	long m=rd();
	rep(i,m){
		ulong a=rd();
		ulong b=rd();
		ulong w=rd();
		e0[i]=w|a<<27|b<<44;
	}
	radix_sort_aux(e0,e1,m,0);
	radix_sort_aux(e1,e0,m,0);
	radix_sort_aux(e0,e1,m,1);
	uf_init();
	ulong z=0;
	rep(i,m){
		ulong e=e1[i];
		long a=uf_root(e>>27&0x1ffff);
		long b=uf_root(e>>44&0x1ffff);
		if(a!=b){
			z+=(e&0x7ffffff)*ufbuf[a]*ufbuf[b];
			uf_unite(a,b);
		}
	}
	wt1(z);
	_exit(0);
}