Simple Python Solution without sorting beats 100%
\n\tdef largestPerimeter(self, A):\n\t\ta = max(A)\n        A.remove(a)\n        b = max(A)\n        A.remove(b)\n        c = max(A)\n        A.remove(c)       
\n\tdef largestPerimeter(self, A):\n\t\ta = max(A)\n        A.remove(a)\n        b = max(A)\n        A.remove(b)\n        c = max(A)\n        A.remove(c)        \n        while b+c <= a and A != []:\n\t\t\ta,b,c = b,c,max(A)\n\t\t   A.remove(c)        \n        if b+c>a: \n            return a+b+c\n        else:\n            return 0
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