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@gauravkr0071
Created August 12, 2021 17:18
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3 sum smaller
/*
259: 3Sum Smaller
Given an array of n integers nums and a target, find the number of index triplets i, j, k with 0 <= i < j < k < n that satisfy the condition nums[i] + nums[j] + nums[k] < target.
For example, given nums = [-2, 0, 1, 3], and target = 2.
Return 2. Because there are two triplets which sums are less than 2:
[-2, 0, 1]
[-2, 0, 3]
Follow up:
Could you solve it in O(n^2) runtime?
*/
public class Solution {
public int threeSumSmaller(int[] nums, int target) {
int L = nums.length;
Arrays.sort(nums);
int count = 0;
for(int i=0; i<L-2; i++) {
int lo = i+1;
int hi = L-1;
while(lo<hi) {
if(nums[i] + nums[lo] + nums[hi] < target) {
count += hi-lo;
lo++;
}
else
hi--;
}
}
return count;
}
}
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