#define MAX_M 100000

#include <iostream>
#include <fstream>

using namespace std;

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

int n, m, k, A[MAX_M + 1], B[MAX_M + 1];

int main()
{
    fin >> n >> m >> k;
    
    for (int i = 1; i <= m; ++i)
        fin >> A[i] >> B[i];
    
    for (int i = m; i >= 1; --i)
    {
        if (k >= A[i])
            k += B[i] - A[i] + 1;
    }
    
    fout << k;
    
    return 0;
}