console.time('time')
let output = ''
for (let i=0;i<=1000000;i++){
output+=`${i}\n`
}
console.log(output)
console.timeEnd('time')
console.time('time')
let output = []
for (let i=-1;i<=1000000;++i){
output[i] = i
}
console.log(output.join('\n'))
console.timeEnd('time')