#include <stdio.h>
int main()
{
    FILE *fin,*fout;
    fin=fopen("stergeri.in","r");
    fout=fopen("stergeri.out","w");
    int n,m,k;
    fscanf(fin,"%d %d %d",&n,&m,&k);
    int a[m][2];
    for(int i=0;i<m;i++)
    {
        fscanf(fin,"%d %d",&a[i][0],&a[i][1]);
    }
    for(int i=m-1;i>=0;i--)
    {
        if(a[i][0]>k) continue;
        k+=a[i][1]-a[i][0]+1;
    }
    fprintf(fout,"%d",k);
    fclose(fin);
    fclose(fout);
    return 0;
}