import java.io.PrintWriter
import java.util.*
import kotlin.math.*

fun PrintWriter.solve() {
    val n = nextInt()
    val m = nextInt()
    val t = nextLong()
    val adj = Array(n) { LongArray(n) { 0 } }
    for (i in 0 until m) {
        val u = nextInt()
        val v = nextInt()
        adj[u][v] = 1
        adj[v][u] = 1
    }
    val mat = Matrix(adj)
    val pow = mat.pow(t).mat
    println(pow[0][0])
}

const val MOD = 998244353L

// region Matrix
class Matrix(val mat: Array<LongArray>) {
    private val n = mat.size

    operator fun plus(other: Matrix): Matrix {
        val b = mat.copyOf()
        for (i in 0 until n) {
            for (j in 0 until n) {
                b[i][j] += other.mat[i][j]
                b[i][j] %= MOD
            }
        }
        return Matrix(b)
    }

    operator fun minus(other: Matrix): Matrix {
        val b = mat.copyOf()
        for (i in 0 until n) {
            for (j in 0 until n) {
                b[i][j] -= other.mat[i][j]
                b[i][j] %= MOD
                b[i][j] += MOD
                b[i][j] %= MOD
            }
        }
        return Matrix(b)
    }

    operator fun times(other: Matrix): Matrix {
        val b = zero(n).mat
        for (k in 0 until n) {
            for (i in 0 until n) {
                for (j in 0 until n) {
                    b[i][j] += mat[i][k] * other.mat[k][j]
                    b[i][j] %= MOD
                }
            }
        }
        return Matrix(b)
    }

    fun pow(exp: Long): Matrix {
        if (exp == 0L) return e(n)
        var a = pow(exp shr 1)
        a *= a
        if (exp and 1L == 0L) return a
        return this * a
    }

    override fun toString(): String {
        return mat.joinToString("\n") { "[${it.joinToString()}]" }
    }
}

fun zero(n: Int): Matrix {
    return Matrix(Array(n) { LongArray(n) { 0 } })
}

fun e(n: Int): Matrix {
    return Matrix(Array(n) { i -> LongArray(n) { j -> if (i == j) 1 else 0 } })
}
// endregion

fun main() {
    Thread(null, {
        val writer = PrintWriter(System.out, false)
        writer.solve()
        writer.flush()
    }, "solve", 1.shl(26))
        .apply { setUncaughtExceptionHandler { _, e -> e.printStackTrace(); kotlin.system.exitProcess(1) } }
        .apply { start() }.join()
}

// region Scanner
private var st = StringTokenizer("")
private val br = System.`in`.bufferedReader()

fun next(): String {
    while (!st.hasMoreTokens()) st = StringTokenizer(br.readLine())
    return st.nextToken()
}

fun nextInt() = next().toInt()
fun nextLong() = next().toLong()
fun nextLine() = br.readLine()
fun nextDouble() = next().toDouble()
// endregion