Here I have a string and an array
String s[] = new String[5]; int num[] = new int [5]; How to convert or write a string to an integer array without using Integer.parseInt (s)?
1 answer
Is this a learning task? Why such a strange restriction? Use new Integer(s) .
If you really pervert, you can try to parse manually:
long result = 0; boolean negative = false; int i = 0, len = s.length(); if (len > 0 && s.charAt[0] == '-') { negative = true; i = 1; } for (; i < len; i++) { char c = s.charAt(i); int digit = (int)c - (int)'0'; if (digit < 0 || digit > 9) throw new IllegalArgumentException("Not a valid digit: '" + c + "'"); result = 10 * result + c; if (result > Integer.MAX_VALUE + 1) // подумайте, почему именно так throw new IllegalArgumentException("Integer overflow"); } if (negative) result = -result; if (result > Integer.MAX_VALUE) throw new IllegalArgumentException("Integer overflow"); return (int)result; 
VladD VladD
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- I am trying to learn java on my own, so to some extent this is a learning task. And there is no limit, I just became curious. - inham130
- Well, if within the framework of curiosity, then you can come up with the following solution, worthy of the best sons from the country of elephants and tea: int crazy_int; if ("1" .equals ("" + 1)) crazy_int = 1; - Chavez
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