let a7 = [[1, 2], [3, 4], [5, 6]];
function t7() {
for (let key in a7) {
console.log(a7[key]);
}
}
t7();
let a7 = [[1, 2], [3, 4], [5, 6]];
function t7() {
var arr = [];
for (let key in a7) {
arr.push(...a7[key]);
}
console.log(arr);
}