需求说明：
1、用两种方法完成如下效果；
2、中间用分页线隔开
代码：
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>统计包含“a”或“A”的字符串的个数</title>
</head>
<body>
<script>
var m=0;
document.write("在以下字符串中:<br/>");
var country=["Amercia","Greece","Britain","Canada","China","Egypt"];
for(var i=0;i<country.length;i++){
document.write(country[i]+"<br/>");
var x=country[i].indexOf("a");
var y=country[i].indexOf("A");
if(x>=0 || y>=0)
m++;
}
document.write("共有"+m+"个字符串包含A或a");
</script>
<hr>
<script type="text/javascript">
document.write("在以下字符串中:<br/>");
var array=["Amercia","Greece","Britain","Canada","China","Egypt"];
var num1=0;
for(var j in array){
document.write(array[j]+"<br>");
if(array[j].indexOf("a")!=-1||array[j].indexOf("A")!=-1){
num1++;
}
}
document.write("共有"+num1+"个字符串包含A或a");
</script>
</body>
</html>
效果图：
