#include"iostream"
#include"stdio.h"
#include"string.h"
#include"algorithm"
using namespace std;
typedef struct f
{
int c;
int m;
int n;
int g;
}F;
bool cmp(F a,F b)
{return a.m<b.m;}
int main()
{
int a,b,i,j,h;
F f[105];
while(~scanf("%d%d",&a,&b))
{int e[105]={0};
for(i=0;i<b;i++)
{scanf("%d%d%d",&f[i].c,&f[i].m,&f[i].n);
f[i].g=i+1;}
sort(f,f+b,cmp);
for(i=0;i<b;i++)
for(i=0;i<b;i++)
{
e[f[i].m]=b+1;
}
for(i=0;i<b;i++)
{h=0;
for(j=f[i].c;j<f[i].m&&h<f[i].n;j++)
{
if(e[j]==0)
{e[j]=f[i].g;h++;}
}
if(h<f[i].n){printf("-1\n");exit(0);}
}
for(i=1;i<=a;i++)
{if(i==a) printf("%d\n",e[i]);
else
printf("%d ",e[i]);}
}
return 0;
}
