senkei.js

<script>


var a=[1,3,5,7];

var b=5;

var i=0;



while(i<4 && b!=a[i]){
  i=i+1;
  }


if(i<4){
  document.write(a[i]);
  }

else{
  
  document.write("失敗");
  }


</script>