问查找重复相邻元素时，字符串索引超出范围？

EN

10101010101010000000101010101010 is valid


01010101010110000000000000000000 is not because there are adjacent 1s

String number;
    boolean valid = false;


    for(int i = 0; i<= 1e32; i++)
    {
         //create binary number
         number = String.format("%32s", Integer.toBinaryString(i)).replace(' ', '0');

         for(int k = 0; k <= number.length() - 1; k++)
         { 
             //check if there are adjacent 1s
             if((number.charAt(k) == '1') && (number.charAt(k+1) == '1'))//I believe error is from this line
             {
                 valid = false;
             }
             else
             {
                 valid = true;
             }
         }
         if(valid == true)
         {
            //Print if there are no adjacent 1s
            System.out.println(number);
            valid = false;
         }
    }

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of    range: 32
at java.lang.String.charAt(String.java:658)
at program.program.main(program.java:30)
Java Result: 1