#[allow(unused_imports)]
use std::cmp::{Ordering};

#[allow(unused_imports)]
use std::collections::{BTreeMap, BTreeSet, BinaryHeap, HashMap, HashSet, VecDeque};

#[allow(unused_imports)]
use std::io::{stdin, stdout, BufWriter, Write};

#[allow(unused_imports)]
use std::iter::FromIterator;

#[allow(unused_macros)]
macro_rules! min {
    ($x: expr) => ($x);
    ($x: expr, $($z: expr),+) => {{
        std::cmp::min($x, min!($($z),*))
    }}
}

#[allow(unused_macros)]
macro_rules! max {
    ($x: expr) => ($x);
    ($x: expr, $($z: expr),+) => {{
        std::cmp::max($x, max!($($z),*))
    }}
}

#[allow(unused_macros)]
macro_rules! get { 
    ([$t: ty]) => { 
        { 
            let mut line = String::new(); 
            stdin().read_line(&mut line).unwrap(); 
            line.split_whitespace().map(|t|t.parse::<$t>().unwrap()).collect::<Vec<_>>()
        }
    };
    ([$t: ty];$n: expr) => {
        (0..$n).map(|_|get!([$t])).collect::<Vec<_>>()
    };
    ($t: ty) => {
        {
            let mut line = String::new();
            stdin().read_line(&mut line).unwrap();
            line.trim().parse::<$t>().unwrap()
        }
    };
    ($($t: ty),*) => {
        { 
            let mut line = String::new();
            stdin().read_line(&mut line).unwrap();
            let mut iter = line.split_whitespace();
            ($(iter.next().unwrap().parse::<$t>().unwrap(),)*)
        }
    };
    ($t: ty; $n: expr) => {
        (0..$n).map(|_|get!($t)).collect::<Vec<_>>()
    };
    ($($t: ty),*; $n: expr) => {
        (0..$n).map(|_|get!($($t),*)).collect::<Vec<_>>()
    };
}

#[allow(unused_macros)]
macro_rules! debug {
    ($($a:expr),*) => {
        #[cfg(debug_assertions)]
        writeln!(&mut std::io::stderr(), concat!("[DEBUG] ", $(stringify!($a), "={:?} "),*), $($a),*).unwrap();
    }
}

const BIG_STACK_SIZE: bool = true;

#[allow(dead_code)]
fn main() {
    use std::thread;
    if BIG_STACK_SIZE {
        thread::Builder::new()
            .stack_size(32 * 1024 * 1024)
            .name("solve".into())
            .spawn(solve)
            .unwrap()
            .join()
            .unwrap();
    } else {
        solve();
    }
}

fn solve() {
    let (n, wl) = get!(usize, usize);
    let mut wv = get!(usize, usize; n);

    let st = wv[0].0;
    wv.sort_by(|&(w1,v1), &(w2,v2)| v2.cmp(&v1));

    let sumw = wv.iter().map(|&(w,_v)| w).sum::<usize>();
    let sumv = wv.iter().map(|&(_w,v)| v).sum::<usize>();
    if wl >= sumw {
        println!("{}", sumv);
        return;
    }
    for i in 0..n {
        wv[i].0 -= st;
    }

    let mut mx = 0;
    for i in 0..(n+1) {
        if (st+3)*i <= wl {
            mx = max!(mx, wv.iter().take(i).map(|&(w,v)| v).sum());
            continue;
        }
        if st*i > wl {
            continue;
        }
        let wlt = wl-st*i;
            
        let mut dp =  vec![vec![vec![0; wlt+1]; i+1]; n+1];
        for j in 0..n {
            for k in 0..i {
                for w in 0..(wlt+1) {
                    dp[j+1][k+1][w] = if w >= wv[j].0 && i > 0 {
                        max!(dp[j][k][w-wv[j].0]+wv[j].1, dp[j][k+1][w])
                    } else {
                        dp[j][k+1][w]
                    };
                }
            }
        }
        mx = max!(mx, *dp[n].iter().map(|e| e.iter().max().unwrap()).max().unwrap());
    }

    println!("{}", mx);
}


Measured memory_bytes: 10620