#include<stdio.h>

struct interval
{
	int left;
	int right;
};

int main()
{
	int n, m, k;
	interval intervale[100010];

	freopen("stergeri.in", "r", stdin);
	freopen("stergeri.out", "w", stdout);

	scanf("%d%d%d", &n, &m, &k);

	for(int i = 0; i < m; ++i)
	{
		scanf("%d%d", &intervale[i].left, &intervale[i].right);
	}

	while(m)
	{
		if(k > intervale[m].left)
			k += intervale[m-1].right - intervale[m-1].left + 1;
		m--;
	}

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

	return 0;
}