#include<stdio.h>
int i,j,n,m,k,x,y,d,a,f;
int main ()
{
    freopen("stergeri.in","r",stdin);
    freopen("stergeri.out","w",stdout);
    scanf("%d%d%d",&n,&m,&k);
    a=k;
    for(i=1;i<=m;++i)
    {
        scanf("%d%d",&x,&y);
        f=y-x+1+d;
        d=0;
        if(x<=k)
        a+=f;
        if(x>k)
        d=f;
    }
    printf("%d",a);
    return 0;
}/*
#include<stdio.h>
#define DIM 1000001
int i,j,n,m,k,x,y,d,a[DIM],f;
int main ()
{
    freopen("stergeri.in","r",stdin);
    freopen("stergeri.out","w",stdout);
    scanf("%d%d%d",&n,&m,&k);
    for(i=1;i<=n;++i)
    a[i]=i;
    for(i=1;i<=m;++i)
    {
        d=0;
        scanf("%d%d",&x,&y);
        f=y-x;
        for(j=1;j<=n;++j)
        {
            if(j==x)
            {
                j+=f;
                ++j;
            }
            ++d;
            a[d]=a[j];
            
        }
        n-=f;
        --n;
    }
    printf("%d",a[k]);
    return 0;
}
*/