最近的整数

Question

例.

int a = 254;
int b = 25;

int c = (closest integer to `a` that is divisible by `b`)

我怎样才能找到整数c？这个例子的结果是c = 250.

Answer 1

有两种情况需要考虑:

1. 最接近的整数小于或等于a:

   int c1 = a - (a % b);
   

2. 最接近的整数大于a:

   int c2 = (a + b) - (a % b);
   

然后我们需要检查哪个更接近a并返回:

int c;
if (a - c1 > c2 - a) {
    c = c2;
} else {
    c = c1;
}

所以我们可以创建一个closestInteger()这样的方法:

static int closestInteger(int a, int b) {
    int c1 = a - (a % b);
    int c2 = (a + b) - (a % b);
    if (a - c1 > c2 - a) {
        return c2;
    } else {
        return c1;
    }
}

例:

System.out.println(closestInteger(254, 25));
System.out.println(closestInteger(9, 5));

输出:

250
10