P14585.js

const readline = require('readline')
const interface = readline.createInterface(process.stdin)

interface.once('line', line => {
    const candy_count = Number(line.split(' ')[1])
    const baskets = new Set()
    interface.on('line', line => {
        let [x, y] = line.split(' ').map(Number)
        baskets.add(y * 301 + x)
    }).on('close', () => {
        let max_candy = Array.from({ length: 301 * 301 })
        max_candy[0] = 0
        for (let x = 1; x < 301; ++x) {
            max_candy[x] = max_candy[x - 1]
            if (baskets.has(x)) {
                max_candy[x] += Math.max(0, candy_count - x)
            }
        }
        for (let y = 1; y < 301; ++y) {
            max_candy[y * 301] = max_candy[y * 301 - 301]
            if (baskets.has(y * 301)) {
                max_candy[y * 301] += Math.max(0, candy_count - y)
            }
        }
        let max = 0
        for (let y = 1; y < 301; ++y) {
            for (let x = 1; x < 301; ++x) {
                max_candy[y * 301 + x] = Math.max(max_candy[y * 301 - 301 + x], max_candy[y * 301 + x - 1])
                if (baskets.has(y * 301 + x)) {
                    max_candy[y * 301 + x] += Math.max(0, candy_count - x - y)
                }
                if (max_candy[y * 301 + x] > max) {
                    max = max_candy[y * 301 + x]
                }
            }
        }
        console.log(max)
    })
})