網(wǎng)易牛分蘋果
import java.util.Arrays;
import java.util.Scanner;
public class Main {
public static void main(String[] args){
Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt();
int[] cow_apples = new int[n];
int i = 0, sum = 0, tmp = 0;
while (i < n){
tmp = scanner.nextInt();
cow_apples[i++] = tmp;
sum += tmp;
}
if (sum % n != 0){
System.out.println(-1);
return;
}
int target = sum / n;
Arrays.sort(cow_apples);
int count = 0;
for (int j:
cow_apples){
if (((j - target) & 1) == 1){
System.out.println(-1);
return;
}
if (j < target){
count += ((target - j) >> 1);
}
}
System.out.println(count);
}
}
