#include <stdio.h>
FILE *fin, *fout;
int n, m, k;
struct qr
{
       int a;
       int b;
} *v;
int main()
{
    fin = fopen("stergeri.in", "r");
    fout = fopen("stergeri.out", "w");
    fscanf(fin, "%d%d%d", &n, &m, &k);
    v = new qr[m];
    for(int i =0; i< m; i++) fscanf(fin, "%d%d", &v[i].a, &v[i].b);
    for(int i = m-1;i>=0; i--)
    {
            if(v[i].a > k) continue;
            k+=v[i].b-v[i].a+1;
    }
    fprintf(fout, "%d\n", k);
    fclose(fin);
    fclose(fout);
    return 0;
}