Leetcode 96

class Solution {
public:
    int numTrees(int n) {
        int dp[];
        dp[] = ;
        dp[] = ;
        dp[] = ;
        for(int i=;i <= n;i++){
            int sum = ;
            for(int j=;j <= (i-)/;j++){
                sum += dp[j]*dp[i--j]*;
            }
            if(i% == ){
                sum += dp[i/]*dp[i/];
            }
            dp[i] = sum;
        }
        return dp[n];
    }
};

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