#include <cstdio>
using namespace std;

struct interval
{
    int x, y;
};
interval v[100005];

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

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

    for (int i = 1; i <= m; ++i)
    {
        scanf("%d %d", &x, &y);
        v[i].x = x; v[i].y = y;
    }

    for (int i = m; i >= 1; --i)
        if (k >= v[i].x)
            k += v[i].y - v[i].x + 1;

    printf("%d\n", k);
    return 0;
}