C# sieve of eratosthenes
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time 
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```csharp []\npublic class Solution {\n    public int PrimePalindrome(int n) {\n        bool[] prime = new bool[10000001];\n        prime[0] = prime[1] = true;\n\n        for(int i = 2;i*i<=10000000;i++)\n        {\n            if(!prime[i])\n            {\n                for(int j = i*i;j<=10000000;j+=i)\n                {\n                    prime[j] = true;\n                }\n            }\n        }\n\n        for(int i = n;i<=10000000;i++)\n        {\n            if(!prime[i] && IsPalindrom(i))\n            {\n                return i;\n            }\n        }\n\n        return 100030001;\n    }\n\n    bool IsPalindrom(int n)\n    {\n        string str = n.ToString();\n        for(int i = 0;i<str.Length/2;i++)\n        {\n            if(str[i] !=str[str.Length-i-1])\n            {\n                return false;\n            }\n        }\n\n        return true;\n    }\n}\n```
['C#']