#include <bits/stdc++.h>

using namespace std;

#if 1
    #define pv(x) cout<<#x<<" = "<<(x)<<"; ";cout.flush()
    #define pn cout<<endl
#else
    #define pv(x)
    #define pn
#endif

#ifdef INFOARENA
    ifstream in("stergeri.in");
    ofstream out("stergeri.out");
#else
    #define in cin
    #define out cout
#endif

using ll = long long;
using ull = unsigned long long;
using uint = unsigned int;
using ld = long double;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
using pld = pair<ld, ld>;
#define pb push_back
const double PI = 3.14159265358979323846264338327950288419716939937510582097494459230781640628620899862;
const int inf_int = 1e9 + 5;
const ll inf_ll = 1e18 + 5;
const int NMax = 1e2 + 5;
const int dx[] = {-1,0,0,+1}, dy[] = {0,-1,+1,0};

int main() {
    cin.sync_with_stdio(false);
    cin.tie(0);
    int N,M,K;
    in >> N >> M >> K;
    vector<pii> op(M);
    for (auto& o : op) {
        in >> o.first >> o.second;
    }
    reverse(op.begin(), op.end());

    for (auto& o : op) {
        if (o.first <= K) {
            K += o.second - o.first + 1;
        }
    }

    out << K << '\n';
    
    return 0;
}