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Java “lambda expressions not supported at this language level”
...and In Properties Tab set Source Compatibility and Target Compatibility to 1.8 (Java 8)
Screenshot:
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Is there an MD5 Fixed Point where md5(x) == x?
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138
Since an MD5 sum is 128 bits long, any fixed point would necessarily also have to be 128 bits ...
Breaking loop when “warnings()” appear in R
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152
You can turn warnings into errors with:
options(warn=2)
Unlike warnings, errors will interr...
Occurrences of substring in a string
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The last line was creating a problem. lastIndex would never be at -1, so there would be an infinite loop. This can be fixed by moving the last line of code into the if block.
String str = "helloslkhellodjladfjhello";
String findStr = "hello";
int lastIndex = 0;
int count = 0;
while(lastInd...
Efficiency of Java “Double Brace Initialization”?
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How is this fibonacci-function memoized?
...is asked for again. If we define some list, xs=[0..] and later ask for its 100th element, xs!!99, the 100th slot in the list gets "fleshed out", holding the number 99 now, ready for next access.
That is what that trick, "going-through-a-list", is exploiting. In normal doubly-recursve Fibonacci def...
How do I find duplicate values in a table in Oracle?
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Count(*) vs Count(1) - SQL Server
Just wondering if any of you people use Count(1) over Count(*) and if there is a noticeable difference in performance or if this is just a legacy habit that has been brought forward from days gone past?
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set DateTime to start of month
...var now = DateTime.Now;
var startOfMonth = new DateTime(now.Year,now.Month,1);
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Pandas DataFrame Groupby two columns and get counts
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126
Followed by @Andy's answer, you can do following to solve your second question:
In [56]: df.g...