题解 | #数组中重复的数字#
数组中重复的数字
https://www.nowcoder.com/practice/6fe361ede7e54db1b84adc81d09d8524
/**
* 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
*
*
* @param numbers int整型vector
* @return int整型
*/
int duplicate(vector<int>& numbers) {
int len = numbers.size();
int result = -1;
for(int i = 0; i < len; i++){
int number = numbers[i];
// validation check
if (number < 0 || number >= len) {
return -1;
}
if (number != i) {
if(numbers[i] == numbers[number]) {
result = numbers[i];
} else {
numbers[i] ^= numbers[number];
numbers[number] ^= numbers[i];
numbers[i] ^= numbers[number];
}
}
}
return result;
}
