#include <fstream>

using namespace std;

const int NMAX= 100000;

ifstream in( "stergeri.in" );
ofstream out( "stergeri.out" );

struct str
{
    int x, y;
};

str v[NMAX+1];

int main(  )
{
    int N, M, K;
    in >> N >> M >> K;

    for( int i= 1; i<=M; ++i )
    {
        in >> v[i].x >> v[i].y;
    }

    for( int i= M; i>=1; --i )
    {
        if( K >= v[i].x )
        {
            K+= v[i].y - v[i].x + 1;
        }
    }

    out << K << '\n';

    return 0;
}