Algorithm
Problem Name: 976. Largest Perimeter Triangle
Given an integer array nums, return the largest perimeter of a triangle with a non-zero area, formed from three of these lengths. If it is impossible to form any triangle of a non-zero area, return 0.
Example 1:
Input: nums = [2,1,2] Output: 5 Explanation: You can form a triangle with three side lengths: 1, 2, and 2.
Example 2:
Input: nums = [1,2,1,10] Output: 0 Explanation: You cannot use the side lengths 1, 1, and 2 to form a triangle. You cannot use the side lengths 1, 1, and 10 to form a triangle. You cannot use the side lengths 1, 2, and 10 to form a triangle. As we cannot use any three side lengths to form a triangle of non-zero area, we return 0.
Constraints:
3 <= nums.length <= 1041 <= nums[i] <= 106
Code Examples
#1 Code Example with Java Programming
Code -
Java Programming
class Solution {
public int largestPerimeter(int[] nums) {
Arrays.sort(nums);
for (int i = nums.length - 3; i >= 0; i--) {
if (nums[i] + nums[i + 1] > nums[i + 2]) {
return nums[i] + nums[i + 1] + nums[i + 2];
}
}
return 0;
}
}
Input
nums = [2,1,2]
Output
5
#2 Code Example with Javascript Programming
Code -
Javascript Programming
const largestPerimeter = function(nums) {
nums.sort((a, b) => a - b)
for(let i = nums.length - 1; i > 1; i--) {
if(nums[i] < nums[i - 1] + nums[i - 2]> return nums[i - 2] + nums[i - 1] + nums[i]
}
return 0
};
Input
nums = [2,1,2]
Output
5
#3 Code Example with Python Programming
Code -
Python Programming
class Solution:
def largestPerimeter(self, A):
"""
:type A: List[int]
:rtype: int
"""
A.sort()
return ([0] + [a + b + c for a, b, c in zip(A, A[1:], A[2:]) if c < a + b])[-1]
Input
nums = [1,2,1,10]
#4 Code Example with C# Programming
Code -
C# Programming
using System;
namespace LeetCode
{
public class _0976_LargestPerimeterTriangle
{
public int LargestPerimeter(int[] A)
{
Array.Sort(A);
for (int i = A.Length - 3; i >= 0; i--)
{
if (A[i] + A[i + 1] > A[i + 2])
return A[i] + A[i + 1] + A[i + 2];
}
return 0;
}
}
}
Input
nums = [1,2,1,10]