#include <cstdio>
using namespace std;

int dif[100001][4];

int main()
{
    freopen("stergeri.in","r",stdin);
    freopen("stergeri.out","w",stdout);

    int i, n, m, k, x1, x2;

    scanf("%d%d%d",&n,&m,&k);

    for( i = 1; i <= m; ++i ){
            scanf("%d%d",&x1,&x2);
            dif[i][1] = x1;
            dif[i][2] = x2;
            dif[i][3] = dif[i][2] - dif[i][1] + 1;
    }

    x1 = k;
    for( i = m; i >= 1; --i )
    if( dif[i][2]<= x1 || dif[i][1] <= x1 ) x1 += dif[i][3];



    printf("%d",x1);



    return 0;
}