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AC代码
import java.util.*;
class Solution {
private int min = Integer.MAX_VALUE;
private int ans = Integer.MAX_VALUE;
private void updateMin(int a, int b, int c, int target) {
int tmp = abs(a + b + c - target);
if (tmp < min) {
min = tmp;
ans = a + b + c;
}
}
public int threeSumClosest(int[] nums, int target) {
if (nums == null || nums.length < 3) {
return Integer.MAX_VALUE;
}
Arrays.sort(nums);
for (int i = 0; i < nums.length - 2; i++) {
int tmpTarget = target - nums[i];
int left = i + 1;
int right = nums.length - 1;
while (left < right) {
//0
if (nums[left] + nums[right] == tmpTarget) {
return target;
} else if (nums[left] + nums[right] < tmpTarget) {
updateMin(nums[i], nums[left], nums[right], target);
left++;
} else {
updateMin(nums[i], nums[left], nums[right], target);
right--;
}
}
}
return ans;
}
private int abs(int a) {
if (a >= 0) {
return a;
} else {
return -a;
}
}
}
精髓
1.依然是two pointers
