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

#define MMAX 100005

int N, M, K;
vector < pair <int, int> > v;


int main()
{
    freopen("stergeri.in", "r", stdin);
    freopen("stergeri.out", "w", stdout);
    scanf("%d %d %d", &N, &M, &K);
    pair <int, int> tmp;
    for(int i=0; i<M; ++i)
    {
        scanf("%d %d", &tmp.first, &tmp.second);
        v.push_back(tmp);
    }
    for(int i=M-1; i>=0; --i)
        if(K>=v[i].first)
            K+=(v[i].second-v[i].first+1);
    printf("%d\n", K);
    return 0;
}