Java CARD类比较方法

Question

int[] value = new int[5];
boolean result = true;
for(int i = 0; i < 5; i++) {
    value[i] = cards[i].getValue();
}
for(int i = 0; i < 5; i++) {
    for(int j = i;j < 5; j++) {
        if(value[i] == value[j + 1]) {
            result = false;
        }
    }
}
return result;

This code is essentially going to compare the values each card object has, and if two cards in the array have the same value return true. We have 5 cards in each hand and that is why the array length is 5. The getValue method returns an integer which is essentially the value of the card. I don't seem to know what I'm doing wrong to be getting errors on my method.

Answer 1

Your array access is incorrect when you use j + 1 , that will be out of bounds when j is four (at the end of the length for value ). And, I would prefer to use value.length instead of hardcoding. Something like

for (int i = 0; i < value.length - 1; i++) {
    for (int j = i + 1; j < value.length; j++) {
        if (value[i] == value[j]) {
            result = false;
        }
    }
}

Additionally, as pointed out by Tom, in the comments; it is pointless to continue iteration when the result becomes false . You could simply return when it becomes false and avoid the result variable entirely. Like,

for (int i = 0; i < value.length - 1; i++) {
    for (int j = i + 1; j < value.length; j++) {
        if (value[i] == value[j]) {
            return false;
        }
    }
}
return true;

Another option, in Java 8+, would be something like

return IntStream.of(value).allMatch(x -> value[0] == x);