#include <cstdio>

using namespace std;
struct Coord
{
    int x,y;
} v[100005];
int main()
{   freopen("stergeri.in", "r",stdin);
    freopen("stergeri.out", "w",stdout);
    int n,m,k,i;
    scanf("%d%d%d", &n, &m, &k);
    for(i=1; i<=m; i++)
        scanf("%d%d", &v[i].x, &v[i].y);
    for(i=m; i>0; i--)
        if(k>v[i].x)
            k+=v[i].y-v[i].x+1;
    printf("%d", k);
    return 0;
}