#include "iostream"
#include "climits"
#include "list"
#include "queue"
#include "stack"
#include "set"
#include "functional"
#include "algorithm"
#include "string"
#include "map"
#include "unordered_map"
#include "unordered_set"
#include "iomanip"
#include "cmath"
#include "random"
#include "bitset"
#include "cstdio"
#include "numeric"
#include "cassert"

using namespace std;

//const long long int MOD = 1000000007;
const int MOD = 998244353;

//long long int N, M, K, H, W, L, R;
int N, M, K, H, W, L, R;

void Solve(vector<vector<int>>&box, int num, vector<int>&st) {
	auto by = box;
	bool flag = true;
	for (int i = 0; i < 12; i++) {
		if ((num >> i) & 1) {
			if (flag) {
				by = box;
			}
			else {
				auto bag = by;
				for (int j = 0; j < N; j++) {
					for (int k = 0; k < N; k++) {
						by[j][k] = 0;
						for (int l = 0; l < N; l++) {
							by[j][k] = ((long long int)bag[j][l] * box[l][k] + by[j][k]) % MOD;
						}
					}
				}
			}
		}
		auto bag = box;
		for (int j = 0; j < N; j++) {
			for (int k = 0; k < N; k++) {
				box[j][k] = 0;
				for (int l = 0; l < N; l++) {
					box[j][k] = ((long long int)bag[j][l] * bag[l][k] + box[j][k]) % MOD;
				}
			}
		}
	}
	auto bag = st;
	for (int j = 0; j < N; j++) {
		for (int k = 0; k < N; k++) {
			st[j] = ((long long int)bag[k] * by[j][k] + st[j]) % MOD;
		}
	}
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);

	cin >> N >> M >> K;
	vector<pair<int, int>>v(M);
	for (auto &i : v) {
		cin >> i.first >> i.second;
		i.first--;
		i.second--;
	}
	vector<int>st(N);
	st[0] = 1;
	vector<vector<int>>box(N, vector<int>(N));
	for (int i = 0; i < N; i++) {
		for (auto j : v) {
			if (j.first > i || j.second < i)continue;
			box[j.first][i]++;
			if (j.second + 1 != N)box[j.second + 1][i]--;
		}
	}
	for (int i = 0; i < N; i++) {
		for (int j = 1; j < N; j++) {
			box[j][i] += box[j - 1][i];
		}
	}
	Solve(box, K, st);
	cout << st.back() << endl;
	return 0;
}