I get a strange problem on some android phones, when I run the code below.
public void test(){
int num = 1;
for(int i=0;i<14;i++){
num = num+100000;
}
System.out.println("num "+num);
}
I expect the answer "1400001", but I get the wrong answer "200385" on the
phone like MotoX 2ndGen, Xiaomi3, Xiaomi note etc.
The strangest thing is that I can get the right answer when I want to debug
it, or complicate the code like
public void test(){
int num = 1;
for(int i=0;i<14;i++){
num = num+100000;
System.out.println("num "+num);
}
}
or
public void test(){
int num1 = 1;
for(int i=0;i<14;i++){
num1 = num1+100000;
}
System.out.println("num1 "+num1);
int num2 = 1;
for(int i=0;i<14;i++){
num2 = num2+100000;
}
System.out.println("num2 "+num2);
}
or turn `int` to `long`, or make "100000" to 100, it can get the right
answer usually. So what is the reason behind this phenomenon? An integer
overflow maybe?
supplement:
I test Integer.SIZE
<https://developer.android.com/reference/java/lang/Integer.html#SIZE> on
the wrong phones is 32 , and the Integer.MAX_VALUE
<https://developer.android.com/reference/java/lang/Integer.html#MAX_VALUE> is
2147483647,as others.And I find that one of results would overflow on
"131072" ，changing to binary is 2^17.And all of the wrong result occur on
fourfold times in "for" code,like the fourth , the eighth etc.so why?
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