#include <fstream>

using namespace std;

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

int n, m, k;

class myClass
{
public:
    int x, y;
};

myClass ans[200005];

int main()
{
    fin >> n >> m >> k;
    for(int i=1; i<=m; i++)
        fin >> ans[i].x >> ans[i].y;

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

    fout << k;

    return 0;
}