#![allow(unused_parens)]
#![allow(unused_imports)]
#![allow(non_upper_case_globals)]


macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
    ($($r:tt)*) => {
        let mut s = {
            use std::io::Read;
            let mut s = String::new();
            std::io::stdin().read_to_string(&mut s).unwrap();
            s
        };
        let mut iter = s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
}

macro_rules! input_inner {
    ($iter:expr) => {};
    ($iter:expr, ) => {};

    ($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    };
}

macro_rules! read_value {
    ($iter:expr, ( $($t:tt),* )) => {
        ( $(read_value!($iter, $t)),* )
    };

    ($iter:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
    };

    ($next:expr, [$t:tt]) => {
        {
            let len = read_value!($next, usize);
            (0..len).map(|_| read_value!($next, $t)).collect::<Vec<_>>()
        }
    };
    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };

    ($iter:expr, usize1) => {
        read_value!($iter, usize) - 1
    };

    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}


#[cfg(debug_assertions)]
macro_rules! mydbg {
    //($arg:expr) => (dbg!($arg))
    ($arg:expr) => (println!("{:?}",$arg));
}


#[cfg(not(debug_assertions))]
macro_rules! mydbg {
    ($($arg:expr),*) => {};
}


use std::cmp;
use std::collections::HashMap;





fn main() {

    input! { 
       n: usize,
       h: i64,
       sord : [(i64,i64);n],
    }

    let mut ans = 0;

    let mut sord0 = vec![(0,0,0);n];
    let mut sord1 = vec![(0,0);n];
    let mut sord2 = vec![(0,0);n];

    let mut sord = sord;

    for i in 0..n{
        sord0[i] = (i,sord[i].0, sord[i].1);
    }

    sord0.sort_by(|a,b|{
        if(a.1 < b.1) {cmp::Ordering::Greater}
        else if(a.1==b.1){cmp::Ordering::Equal}
        else{cmp::Ordering::Less}
    });

    for i in 0..n{
        sord1[i] = (sord0[i].0,sord0[i].1);
    }

    sord0.sort_by(|a,b|{
        if(a.2 < b.2) {cmp::Ordering::Greater}
        else if(a.2==b.2){cmp::Ordering::Equal}
        else{cmp::Ordering::Less}
    });

    
    for i in 0..n{
        sord2[i] = (sord0[i].0,sord0[i].2);
    }

   
   mydbg!(sord1);
   mydbg!(sord2);
   let mut h = h;
   
   let damage = sord1[0];
   for i in 0..n{
       let s = sord2[i];
       if(s.0 == damage.0){
           continue;
       }
       if(s.1 > damage.1){
           h -= s.1;
           ans+=1;
       }
       else{
           break;
       }

       if(h<=0){
           break;
       }
   }

    let last = sord[damage.0].1 > sord[damage.0].0;
    let last_d = sord[damage.0].1;



   if(h>0){
        let tmp = h / damage.1;
        ans += tmp-1;
        h -= (tmp-1) * damage.1;
       while(true){
           if( last == true && h <= last_d){
               h-=last_d;
           }
           else{
                h-=damage.1;
           }
           ans+=1;
           if(h<=0){
               break;
           }
       }
   }


   
   
    
    
    println!("{}",ans);


}
