import sys input = sys.stdin.readline class LazySegTree: def __init__(self, n, op, e, mapping, composition, id): self.n = n self.op = op self.e = e self.mapping = mapping self.composition = composition self.id = id self.log = (n-1).bit_length() self.size = 1 << self.log self.data = [e]*(2*self.size) self.lazy = [id]*(self.size) def update(self, k): self.data[k] = self.op(self.data[2*k],self.data[2*k+1]) def build(self, lis): for i, l in enumerate(lis,self.size): self.data[i] = l for i in range(self.size-1, 0, -1): self.update(i) def point_set(self, p, x): p += self.size for i in range(self.log, 0, -1): self.push(p >> i) self.data[p] = x for i in range(1,self.log+1): self.update(p>>i) def point_get(self, p): p += self.size for i in range(1, self.log+1): self.push(p >> i) return self.data[p] def apply(self, p, f): p += self.size for i in range(self.log, 0, -1): self.push(p >> i) self.data[p] = self.mapping(f, self.data[p]) for i in range(1, self.log+1): self.update(p >> i) def range_apply(self, l, r, f): ''' change the value you define in "mapping" and "composition" of [l,r) ''' if l == r: return l += self.size r += self.size for i in range(self.log, 0, -1): if ((l >> i) << i) != l: self.push(l >> i) if ((r >> i) << i) != r: self.push((r-1) >> i) l2 = l r2 = r while l2 < r2: if l2 & 1: self.all_apply(l2, f) l2 += 1 if r2 & 1: r2 -= 1 self.all_apply(r2, f) l2 >>= 1 r2 >>= 1 for i in range(1, self.log+1): if ((l >> i) << i) != l: self.update(l >> i) if ((r >> i) << i) != r: self.update((r-1) >> i) def all_apply(self, k, f): self.data[k] = self.mapping(f, self.data[k]) if k < self.size: self.lazy[k] = self.composition(f, self.lazy[k]) def push(self, k): self.all_apply(2*k, self.lazy[k]) self.all_apply(2*k+1, self.lazy[k]) self.lazy[k] = self.id def prod(self, l, r): ''' get the value you define in "op" of [l,r) ''' if l == r: return self.e l += self.size r += self.size for i in range(self.log, 0, -1): if ((l>>i) <>i) if ((r>>i) <>i) sml = smr = 10**10 while l < r: if l & 1: sml = self.op(sml, self.data[l]) l += 1 if r & 1: r -= 1 smr = self.op(self.data[r], smr) l >>= 1 r >>= 1 return self.op(sml, smr) def all_prod(self): return self.data[1] def op(x, y): return max(x,y) def mapping(p, x): return max(x,p) def composition(p, q): return max(p,q) class SegTree: """ define what you want to do with 0 index, ex) size = tree_size, func = min or max, sta = default_value """ def __init__(self,size,func,sta): self.n = size self.size = 1 << size.bit_length() self.func = func self.sta = sta self.tree = [sta]*(2*self.size) def build(self, list): """ set list and update tree""" for i,x in enumerate(list,self.size): self.tree[i] = x for i in range(self.size-1,0,-1): self.tree[i] = self.func(self.tree[i<<1],self.tree[i<<1 | 1]) def set(self,i,x): i += self.size self.tree[i] = x while i > 1: i >>= 1 self.tree[i] = self.func(self.tree[i<<1],self.tree[i<<1 | 1]) def get(self,l,r): """ take the value of [l r) with func (min or max)""" l += self.size r += self.size res = self.sta while l < r: if l & 1: res = self.func(self.tree[l],res) l += 1 if r & 1: res = self.func(self.tree[r-1],res) l >>= 1 r >>= 1 return res def f(x,y): return min(x,y) e = 1 id = 0 n,q = map(int,input().split()) lazyseg = LazySegTree(n, op, e, mapping, composition, id) Q = [list(map(int,input().split())) for i in range(q)] for l,r,b in Q: lazyseg.range_apply(l-1,r,b) ans = [lazyseg.point_get(i) for i in range(n)] seg = SegTree(n,f,10**9) seg.build(ans) for l,r,b in Q: if seg.get(l-1,r) != b: print(-1) exit() print(*ans)