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#include <iostream>
#include <vector>
#include <cmath>

using namespace std;

const int MAXM = 1005;
long long n, s;
int m;
vector<long long> l(MAXM), r(MAXM);

int find(long long x) {
	for(int i = 0; i < m; i++) {
		if(l[i] <= x && x <= r[i]) {
			return i;
		}
	}
	return -1;
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(0);

	cin >> n >> m >> s;
	for(int i = 0; i < m; i++) {
		cin >> l[i] >> r[i];
	}
	
	long long left = s, right = s;
	while(true) {
		int ind = find(left);
		if(ind == -1) break;
		
		left = l[ind]-1;
	}
	
	while(true) {
		int ind = find(right);
		if(ind == -1) break;
		
		right = r[ind]+1;
	}
	
	long long ans;
	
	if(left < 1) ans = right;
	else if(right > n) ans = left;
	else {
		if(abs(s-left) <= abs(s-right)) ans = left;
		else ans = right;
	}
	
	cout << ans << "\n";
	
	return 0;
}