<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<script>
var row = prompt('请你输入行数');
var col = prompt('请你输入列数');
var str = '';
for (var i = 1; i <= row; i++) {
for (var j = 1; j <= col; j++) {
str = str + '★';
}
str += '\n';
}
console.log(str);
</script>
</head>
<body>
</body>
</html>