#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define rep(i, a, b) for(int i=(a); i<(b); i++)
#define sz(x) (int)x.size()
#define de(x) cout<< #x<<" = "<<x<<endl
#define dd(x) cout<< #x<<" = "<<x<<" "
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

const int N=1000007, S=N-4;

int n,m;
int cnt[N<<1], ans[N], pre[N<<1];
bool vis[N];

void upd(int p,int c) {
    for(int i=p;i<=S+S;i+=(i&-i)) cnt[i]+=c;
}
int qry(int p) {
    int res=0;
    for(int i=p;i;i-=(i&-i)) res+=cnt[i];
    return res;
}

int main() {
    scanf("%d%d",&n,&m);
    rep(i,1,S+1) upd(i+S, 1);
    int p=S;
    rep(i,1,m+1) {
        int v, x;scanf("%d%d",&v,&x);
        int l=1, r=S+S, res=-1;
        while(l<=r) {
            int mid=l+r>>1;
            if(qry(mid)<x) {
                res=mid+1;
                l=mid+1;
            } else {
                r=mid-1;
            }
        }
        if(res>S) {
            if(vis[v]) {
                puts("-1");
                return 0;
            }
            vis[v]=1;
            ans[res-S]=v;
        } else {
            if(pre[res]!=v) {
                puts("-1");
                return 0;
            }
        }
        upd(res, -1);
        upd(p, 1);
        pre[p]=v;
        --p;
    }
    for(int i=1,j=1;i<=n;++i) if(!ans[i]) {
        while(vis[j]) ++j;
        ans[i]=j;
        vis[j]=1;
    }
    rep(i,1,n+1) printf("%d%c",ans[i]," \n"[i==n]); 
    return 0;
}