Interestingly in Java, at the language level, string concatenation is translated like this: x + "s" + y + "t" + z --> new java.lang.StringBuilder(

Interestingly in Java, at the language level, string concatenation is translated like this: x + "s" + y + "t" + z --> new java.lang.StringBuilder().append(x).append("s").append(y).append("t").append(z).toString() and not naively like this: java.lang.String.valueOf(x).concat("s").concat(String.valueOf(y)).concat("t").concat(String.valueOf(z)) > just learn str.join() Or Python io.StringIO .