#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
const int maxn=100010;
const int maxm=300010;
int f[maxn],g[maxn],siz[maxn],st[maxn],ans[maxm];
int n,m,cnt,top;
struct edge
{int a,b,c,tim;
}p[maxm],q[maxm];
bool cmp(const edge &a,const edge &b)
{return (a.c==b.c)?(a.tim<b.tim):(a.c<b.c);
}
inline void uni(int a,int b)
{int x=a,y=b,c=0,d=0;while(f[x]!=x)    x=f[x],c++;while(f[y]!=y)   y=f[y],d++;if(x==y)    return ;if(c>d)  swap(x,y),swap(a,b);cnt-=(siz[x]&1)+(siz[y]&1)-((siz[x]+siz[y])&1);siz[y]+=siz[x],f[x]=y;st[++top]=x;
}
inline void del(int x)
{int y=f[x];siz[y]-=siz[x],f[x]=x;cnt+=(siz[x]&1)+(siz[y]&1)-((siz[x]+siz[y])&1);
}
void solve(int l,int r,int L,int R)
{if(l>r) return ;int mid=(l+r)>>1,i,now=top,MID;for(i=l;i<=mid;i++)  if(p[i].c<=L)   uni(p[i].a,p[i].b);for(i=L;i<=R&&cnt;i++)    if(q[i].tim<=mid)   uni(q[i].a,q[i].b);MID=max(L,i-1);if(!cnt) ans[p[mid].tim]=q[MID].c;else  ans[p[mid].tim]=-1;while(top>now)   del(st[top--]);for(i=L;i<=MID;i++)   if(q[i].tim<=l) uni(q[i].a,q[i].b);solve(l,mid-1,MID,R);while(top>now)   del(st[top--]);for(i=l;i<=mid;i++)   if(p[i].c<=L)   uni(p[i].a,p[i].b);solve(mid+1,r,L,MID);while(top>now)  del(st[top--]);
}
inline int rd()
{int ret=0,f=1;   char gc=getchar();while(gc<'0'||gc>'9')  {if(gc=='-')    f=-f;  gc=getchar();}while(gc>='0'&&gc<='9')  ret=ret*10+(gc^'0'),gc=getchar();return ret*f;
}
int main()
{n=rd(),m=rd();int i;for(i=1;i<=m;i++) p[i].a=rd(),p[i].b=rd(),p[i].c=rd(),p[i].tim=i,q[i]=p[i];sort(q+1,q+m+1,cmp);for(i=1;i<=n;i++)   f[i]=i,siz[i]=1;for(i=1;i<=m;i++)  p[q[i].tim].c=i;cnt=n;solve(1,m,1,m);for(i=1;i<=m;i++) printf("%d\n",ans[i]);return 0;
}