javascript 实现 radio 的联动

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<script>
function checkradio(o,x){
document.getElementsByName("inptB")[x-1].checked=o.checked
}
</script>
<input name="inptA" type="radio" id="inptA" onclick="checkradio(this,1)">aaa
<input name="inptA" type="radio" id="inptA" onclick="checkradio(this,2)">bbb
<input name="inptA" type="radio" id="inptA" onclick="checkradio(this,3)">ccc
<br>
<input name="inptB" type="radio" id="inptB">111
<input name="inptB" type="radio" id="inptB">222
<input name="inptB" type="radio" id="inptB">333