#include <stdio.h>
#include <algorithm>

using namespace std;

const int N_MAX = 100010;

pair <int, int> v[N_MAX];

int main()
{
	freopen("stergeri.in", "r", stdin);
#ifndef _SCREEN_
	freopen("stergeri.out", "w", stdout);
#endif

	int N, M, K, i;
	scanf("%d %d %d\n", &N, &M, &K);

	int x, y;
	for (i = 1; i <= M; i ++) {
		scanf("%d %d\n", &x, &y);
		v[i] = make_pair(x, (y - x + 1));
	}

	for (i = M; i >= 1; i --) {
		if (K >= v[i].first) K += v[i].second;
	}

	printf("%d\n", K);

	return 0;
}