Javscript Array filtering

Student information define the name of the two-dimensional array
(' Small a ', ' female ', 21, ' Freshman '), (' Little b ', ' Male ', 23, ' Junior '),

(' small c ', ' Male ', 24, ' Senior '), (' Small d ', ' female ', 21, ' freshman '),

(' small e ', ' female ', 22, ' Senior '), (' Small f ', ' male ', 21, ' freshman '),

(' small g ', ' female ', 22, ' sophomore '), (' Little h ', ' female ', 20, ' Junior '),

(' Small I ', ' female ', 20, ' Freshman '), (' Little J ', ' Male ', 20, ' Junior ')
To delete the student information of the female freshman
The first of these methods
var info = [[' Small A ', ' female ', 21, ' freshman '], [' small B ', ' Male ', 23, ' Junior '],
[' Small C ', ' Male ', 24, ' senior '], [' small d ', ' female ', 21, ' freshman '],
[' small e ', ' female ', 22, ' senior '], [' Small f ', ' male ', 21, ' freshman '],
[' small g ', ' female ', 22, ' sophomore '], [' Little H ', ' female ', 20, ' Junior '],
[' Small I ', ' female ', 20, ' freshman '], [' Little J ', ' Male ', 20, ' Junior '];
var num = 0,key = 0;
var infos = new Array ();
for (Var i=0;i<5;i++) {
Infos[i] = new Array ();
for (Var j=0;j<2;j++) {
INFOS[I][J] = Info[num];
num++;
if (infos[i][j][3] = = "Freshman") {
document.write (Infos[i][j]);
document.write ("<br/>");
Info[key] = Infos[i][j];
key++;
}
}
}
document.write ("<br/> secondary screening: <br/>")
for (var q = 0;q < key;q++) {
if (info[q][1] = = "female") {
document.write (Info[q]);
document.write ("<br/>");
}
}
The second method of
var infos = [
[' Small a ', ' female ', 21, ' freshman '],
[' small B ', ' Male ', 23, ' Junior '],
[' Small C ', ' Male ', 24, ' senior '],
[' Small C ', ' Male ', 24, ' senior '],
[' small d ', ' female ', 21, ' freshman '],
[' small e ', ' female ', 22, ' senior '],
[' Small f ', ' male ', 21, ' freshman '],
[' small g ', ' female ', 22, ' sophomore '],
[' Little H ', ' female ', 20, ' Junior '],
[' Small I ', ' female ', 20, ' freshman '],
[' Little J ', ' Male ', 20, ' juniors ']
];
document.write ("The first" + "<br>");
First screening, finding all the information that's a freshman.
for (Var i=0;i<infos.length;i++)
{
if (infos[i][3] = = "Freshman") {
for (Var j=0;j<infos[i].length;j++)
document.write (infos[i][j]+ "");
document.write ("<br>");}
}

document.write ("The second" + "<br>")
Second screening, find out all the girls ' information
for (Var i=0;i<infos.length;i++)
{
if (infos[i][1] = = "female") {
for (Var j=0;j<infos[i].length;j++)
document.write (infos[i][j]+ "");
document.write ("<br>");}
}
The third method of
var infos = [
[' Small a ', ' female ', 21, ' freshman '],
[' small B ', ' Male ', 23, ' Junior '],
[' Small C ', ' Male ', 24, ' senior '],
[' Small C ', ' Male ', 24, ' senior '],
[' small d ', ' female ', 21, ' freshman '],
[' small e ', ' female ', 22, ' senior '],
[' Small f ', ' male ', 21, ' freshman '],
[' small g ', ' female ', 22, ' sophomore '],
[' Little H ', ' female ', 20, ' Junior '],
[' Small I ', ' female ', 20, ' freshman '],
[' Little J ', ' Male ', 20, ' juniors ']
];
for (var i = 0; i < infos.length; i++)
{
if (infos[i][3] = = = "Freshman" && infos[i][1] = = = "female")
{
for (Var j=0;j<infos[i].length;j++)
document.write (Infos[i][j]);
document.write ("<br>");
}
}

Javscript Array Filter