// CERC 2012
// Problem J: Conservation
// Model solution.
// Author: Jakub Pachocki

import java.io.*;
import java.util.*;

import sun.misc.Queue;

class Solver {
	
	void solve() throws IOException {
		Reader.init(System.in);
		int nCases = Reader.nextInt();
		for (int testCase = 0; testCase < nCases; ++testCase) {
			int n = Reader.nextInt();
			int m = Reader.nextInt();
			int[] lab = new int[n];
			for (int i = 0; i < n; ++i) {
				lab[i] = Reader.nextInt();
			}
			ArrayList<Integer>[] e = new ArrayList[n];
			for (int i = 0; i < n; ++i) {
				e[i] = new ArrayList<Integer>();
			}
			for (int i = 0; i < m; ++i) {
				int a = Reader.nextInt();
				int b = Reader.nextInt();
				--a;
				--b;
				e[a].add(b);
			}
			int result = n;
			for (int start = 1; start <= 2; ++start) {
				int[] indeg = new int[n];
				for (int i = 0; i < n; ++i) {
					for (int j: e[i]) {
						++indeg[j];
					}
				}
				java.util.Deque<Integer> q = new ArrayDeque<Integer>();
				for (int i = 0; i < n; ++i) {
					if (indeg[i] == 0) {
						if (lab[i] == start) {
							q.addFirst(i);
						} else {
							q.addLast(i);
						}
					}
				}
				int curLab = start;
				int score = 0;
				while (!q.isEmpty()) {
					int c = q.poll();
					if (lab[c] != curLab) {
						++score;
						curLab = lab[c];
					}
					for (int v: e[c]) {
						if (--indeg[v] == 0) {
							if (lab[v] == curLab) {
								q.addFirst(v);
							} else {
								q.addLast(v);
							}
						}
					}
				}
				result = Math.min(result, score);
			}
			System.out.println(result);
		}
	}
}

public class J {

	public static void main(String[] args) throws IOException {
		(new Solver()).solve();
	}

}

/** Class for buffered reading int and double values */
class Reader {
    static BufferedReader reader;
    static StringTokenizer tokenizer;

    /** call this method to initialize reader for InputStream */
    static void init(InputStream input) {
        reader = new BufferedReader(
                     new InputStreamReader(input) );
        tokenizer = new StringTokenizer("");
    }

    /** get next word */
    static String next() throws IOException {
        while ( ! tokenizer.hasMoreTokens() ) {
            //TODO add check for eof if necessary
            tokenizer = new StringTokenizer(
                   reader.readLine() );
        }
        return tokenizer.nextToken();
    }

    static int nextInt() throws IOException {
        return Integer.parseInt( next() );
    }
	
    static double nextDouble() throws IOException {
        return Double.parseDouble( next() );
    }
}