function twoLines(l1o,l2o) {
    // a -- b  c -- d
    let r = 0
    for(let l1=1;l1<=l1o;l1++) { 
        let l2 = (l1o + l2o - l1)
        for(let a=0;a<10-l2-1;a++) {
            /*let b = a + l1
            console.log(b)
            for (let c=b + 1;c <= (10 - l2);c++) {
                let d = c + l2
                console.log(`${a}--${b} (${b-a}) ${c}--${d} (${d - c})`)
                r++
            }*/
            r += (10 - l2) - (a + l1 + 1) + 1
        }
    }
    return r
}
let r = twoLines(2,2)
console.log(`${r} перестановок`)

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