34. 结对编程

const readline = require('readline');
const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
});

rl.on('line', (line) => {
    rl.on('line', (line) => {
        const levels = levelsStr.split(' ').map(Number);
        console.log(countTeams(parseInt(n,10), levels));
    });
});
function countTeams(n, levels) {
    let ans = 0;
    let smallLeft = new Array(n).fill(0);
    let greatLeft = new Array(n).fill(0);
    let smallRight = new Array(n).fill(0);
    let greatRight = new Array(n).fill(0);

    for(let i=1; i<n; i++) {
        for(let j=0; j<i; j++) {
            if (levels[j] < levels[i]) {
                smallLeft++;
            } else if(levels[j] > levels[i]) {
                greatLeft++;
            }
        }
    }

    for(let i=n-2; i>=0; i--) {
        for(let j=n-1; j>i; j--) {
            if (levels[j] < levels[i]) {
                smallRight++;
            } else if(levels[j] > levels[i]) {
                greatRight++;
            }
        } 
    }

    for(let i=0;i<n; i++) {
        ans += smallLeft[i]*greatRight[i] + greatLeft[i]*smallRight[i];
    }
    return ans;
}