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Ruby: How to get the first character of a string
How can I get the first character in a string using Ruby?
13 Answers
13
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Why can't a text column have a default value in MySQL?
... I try to recreate the table locally with the obvious default (based on a select of unique values for that column) and end up receiving the oh-so-useful BLOB/TEXT column can't have a default value.
Again, not maintaining basic compatability across platforms is unacceptable and is a bug.
How to ...
How to convert floats to human-readable fractions?
...duct of these matrices.
*/
#include <stdio.h>
main(ac, av)
int ac;
char ** av;
{
double atof();
int atoi();
void exit();
long m[2][2];
double x, startx;
long maxden;
long ai;
/* read command line arguments */
if (ac != 3) {
fprintf(stderr, "usage...
Java - Convert integer to string [duplicate]
...m a
* @return
*/
private String convertToString(int a) {
int c;
char m;
StringBuilder ans = new StringBuilder();
// convert the String to int
while (a > 0) {
c = a % 10;
a = a / 10;
m = (char) ('0' + c);
ans.append(m);
}
return ans.re...
Divide a number by 3 without using *, /, +, -, % operators
...* fp=fopen("temp.dat","w+b");
int number=12346;
int divisor=3;
char * buf = calloc(number,1);
fwrite(buf,number,1,fp);
rewind(fp);
int result=fread(buf,divisor,number,fp);
printf("%d / %d = %d", number, divisor, result);
free(buf);
fclose(fp);
return 0;
}
If...
How to convert hex to rgb using Java?
...
For those who want a 3 character version as well, note that in the 3 character case each value must be * 255 / 16. I tested this with "000", "aaa", and "fff", and they all work properly now.
– Andrew
Apr 14 '...
Integrating the ZXing library directly into my Android application
......
Navigate to the newly extracted folder and open the core directory and select core.jar ... hit enter!
Now you just have to correct a few errors in the translations and the AndroidManifest.xml file :) Now you can happily compile, and you will now have a working standalone barcode scanner app, b...
In .NET, which loop runs faster, 'for' or 'foreach'?
...
Enumerable.Select has an overload that lets you obtain the index of the item, so even the need for an index does not mandate using for. See msdn.microsoft.com/en-us/library/bb534869.aspx
– TrueWill
...
Which one will execute faster, if (flag==0) or if (0==flag)?
...is a user-defined type. Then it depends on which overload of operator== is selected. Of course it can seem stupid that they would not be symmetric, but it's certainly allowed, and I have seen other abuses already.
If flag is a built-in, then both should take the same speed.
From the Wikipedia arti...
How to check whether a file is empty or not?
... my_file.seek(0) #ensure you're at the start of the file..
... first_char = my_file.read(1) #get the first character
... if not first_char:
... print "file is empty" #first character is the empty string..
... else:
... my_file.seek(0) #first character wasn't empty, retu...