#include <bits/stdc++.h>

int ri() {
	int n;
	scanf("%d", &n);
	return n;
}

std::vector<std::vector<int> > hen;
std::vector<int> ord;
std::vector<bool> visited;
int cnt;
void dfs(int i) {
	visited[i] = true;
	for (auto j : hen[i]) {
		if (visited[j]) continue;
		dfs(j);
	}
	ord[i] = --cnt;
}

bool solve(int n, int m, const int *a) {
	for (int i = 0; i + 2 < n; i++) if (a[i] == a[i + 2]) return false;
	hen.resize(m);
	for (int i = 0; i + 1 < n; i++) {
		if (i & 1) hen[a[i]].push_back(a[i + 1]);
		else hen[a[i + 1]].push_back(a[i]);
	}
	ord.resize(m, -1);
	visited.resize(m, false);
	cnt = m;
	for (int i = 0; i < m; i++)
		if (!visited[i]) dfs(i);
	for (int i = 0; i < m; i++)
		for (auto j : hen[i]) if (ord[j] <= ord[i]) return false;
	return true;
}

int main() {
	int n = ri();
	int m = ri();
	int a[n];
	for (int i = 0; i < n; i++) a[i] = ri() - 1;
	
	
	if (!solve(n, m, a)) puts("No");
	else {
		puts("Yes");
		for (int i = 0; i < m; i++) {
			if (i) printf(" ");
			printf("%d", ord[i] + 1);
		}
		puts("");
	}
	return 0;
}