#include <cstdio>
#include <algorithm>
using namespace std;

const int MMAX = 100003;

int A[MMAX], B[MMAX];

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", A + i, B + i);
    for (i = M; i; --i)
        if (K >= A[i])
            K += B[i] - A[i] + 1;
    printf ("%d", K);

}