#include<iostream>
#include<cstdio>

using namespace std;

int st[100000], dr[100000];
int main()
{
    FILE *fin, *fout;
    fin=fopen("stergeri.in", "r");
    fout=fopen("stergeri.out", "w");

    int n, m, k, i;
    fscanf(fin, "%d %d %d", &n, &m, &k);
    for(i=0; i<m; i++)
        fscanf(fin, "%d %d", &st[i], &dr[i]);
    for(i=m-1; i>=0; i--)
    {
        if(st[i]<=k)
            k+=(dr[i]-st[i]+1);
    }
    fprintf(fout, "%d", k);

}