public class Program {
	public static void Main() {
        var linhas = 3;
        var colunas = 3;
        var matriz = new int[linhas, colunas];
        for (int i = 0, count = 0; i < linhas; i++) for (int j = 0; j < colunas; j++) matriz[i, j] = count++;
        var vetor = new int[matriz.Length];
        for (int i = 0, count = 0; i < linhas; i++) for (int j = 0; j < colunas; j++) vetor[count++] = matriz[i, j];
	}
}
 
//https://pt.stackoverflow.com/q/431651/101

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