Tmp2 - Revision history

Root: /* Keep complications to minimum */

2007-04-09T18:02:59Z

Keep complications to minimum

← Older revision		Revision as of 18:02, 9 April 2007
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	=Good practice in Coding (in C++/C)=		=Good practice in Coding (in C++/C)=
	==Keep complications to minimum==		==Keep complications to minimum==
			* C++ (and many other language) have complicated rules on operator precedence. Remember: YOU DON'T NEED 95% of these rules. Unless it is obvious, use parenthesis, to separeate operations.
			<source lang=cpp>
			a=b/4*x+1 //will give you an answer.
			//If you know what you are doing, fine.
			//But at least for other's sake it is better to write
			a=(b/4)*x+1 // which is the equivalent of above, but much easier to understand.
			a=b/(4*x)+1 // if you want to say THAT
			</source>
	* Use pointers sparingly, there are many situations where they have good alternatives. Make a concious effort to find these alternatives if at all possible. One good example is use of vectors instead of dynamic arrays.		* Use pointers sparingly, there are many situations where they have good alternatives. Make a concious effort to find these alternatives if at all possible. One good example is use of vectors instead of dynamic arrays.
	{\|		{\|
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	</source>		</source>
	\|}		\|}

	==Variables==		==Variables==
	* Define variables with minimum scope. If you just need a variable to use for a counter in a loop, don't define it as a global variable. In <tt>for</tt> loops define the counter within the <tt>for</tt> statement. And when you have to define a global variable, use a good descriptive name.		* Define variables with minimum scope. If you just need a variable to use for a counter in a loop, don't define it as a global variable. In <tt>for</tt> loops define the counter within the <tt>for</tt> statement. And when you have to define a global variable, use a good descriptive name.

Root: /* Loops */

2007-04-09T15:59:41Z

Loops

← Older revision		Revision as of 15:59, 9 April 2007
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	} // end of loop cti		} // end of loop cti
	</source>		</source>

			==Structure==
			* Use functions to modularize your code.
			* Do not re-invent the wheel. First see whether there is a standard function to do something (for many simple calculations there is), before writing one yourself.
			*

Root: /* Variables */

2007-04-09T15:54:19Z

Variables

← Older revision		Revision as of 15:54, 9 April 2007
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	\|}		\|}
	==Variables==		==Variables==
	* Define variables with minimum scope. If you just need a variable to use for a counter in a loop, don't define it as a global variable. In <tt>for</tt> loops define the counter within the <tt>for</tt> statement.		* Define variables with minimum scope. If you just need a variable to use for a counter in a loop, don't define it as a global variable. In <tt>for</tt> loops define the counter within the <tt>for</tt> statement. And when you have to define a global variable, use a good descriptive name.
	<source lang=cpp>		<source lang=cpp>
	for(unsigned int i=0;i<vect.size();i++){ // much better than a globally defined i.		for(unsigned int i=0;i<vect.size();i++){ // much better than a globally defined i.
	...		...
	}		}

	</source>		</source>

Root: /* Loops */

2007-04-09T15:53:04Z

Loops

← Older revision		Revision as of 15:53, 9 April 2007
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	..		..
	</source>		</source>
	* Use indenting and comments to make multiple loops easy to read. In long loops like the code shown below it really helps to have the comments like <tt>end of loop i</tt> at the place where the loop is closed.		* Use indenting and comments to make multiple loops easy to read. In long loops like the code shown below it really helps to have the comments like <tt>end of loop cti</tt> at the place where the loop is closed. And the use of 'funny' counters like <tt>cti</tt> and <tt>jj</tt> is not an accident. In long code, avoid using one letter variable names, unless the scope of these variables are very short -- this make search and find easy.
	<source lang=cpp>		<source lang=cpp>
	for (int i=0;i<n;i++){		for (int cti=0;cti<n;cti++){
	for (int j=0;j<m;j++){		for (int jj=0;jj<m;jj++){
	a=b[i];		a=b[cti];
	//... 559 lines of code -- we don't print them here		//... 559 lines of code -- we don't print them here
	...		...
	} // end of loop j		} // end of loop jj
	//... another 400 lines of code -- again we skip.		//... another 400 lines of code -- again we skip.
	...		...
	} // end of loop i		} // end of loop cti
	</source>		</source>

Root: /* Loops */

2007-04-09T15:50:12Z

Loops

← Older revision		Revision as of 15:50, 9 April 2007
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	a=b[i];		a=b[i];
	//... 559 lines of code -- we don't print them here		//... 559 lines of code -- we don't print them here
			...
	} // end of loop j		} // end of loop j
	//... another 400 lines of code -- again we skip.		//... another 400 lines of code -- again we skip.
			...
	} // end of loop i		} // end of loop i
	</source>		</source>

Root: /* Loops */

2007-04-09T15:49:06Z

Loops

← Older revision		Revision as of 15:49, 9 April 2007
Line 60:		Line 60:
	..		..
	</source>		</source>
	* Use indenting and comments to make multiple loops easy to read.		* Use indenting and comments to make multiple loops easy to read. In long loops like the code shown below it really helps to have the comments like <tt>end of loop i</tt> at the place where the loop is closed.
	<source lang=cpp>		<source lang=cpp>
	for (int i=0;i<n;i++){		for (int i=0;i<n;i++){
	for (int j=0;j<m;j++){		for (int j=0;j<m;j++){
	a=b[i];		a=b[i];
	//... 559 lines of code		//... 559 lines of code -- we don't print them here
	} // end of loop j		} // end of loop j
	//... another 400 lines of code		//... another 400 lines of code -- again we skip.
	} // end of loop i		} // end of loop i
	</source>		</source>

Root: /* Loops */

2007-04-09T15:47:39Z

Loops

← Older revision		Revision as of 15:47, 9 April 2007
Line 65:		Line 65:
	for (int j=0;j<m;j++){		for (int j=0;j<m;j++){
	a=b[i];		a=b[i];
	... 559 lines of code		//... 559 lines of code
	} // end of loop j		} // end of loop j
	... another 400 lines of code		//... another 400 lines of code
	} // end of loop i		} // end of loop i
	</source>		</source>

Root at 15:47, 9 April 2007

2007-04-09T15:47:21Z

@@ Line 1: / Line 1: @@
 =Good practice in Coding (in C++/C)=
 * Use pointers sparingly, there are many situations where they have good alternatives. Make a concious effort to find these alternatives if at all possible. One good example is use of vectors instead of dynamic arrays.
 {|
@@ Line 30: / Line 31: @@
 </source>
 |}

Root: /* Good practice in Coding (in C++/C) */

2007-04-09T15:38:04Z

Good practice in Coding (in C++/C)

← Older revision		Revision as of 15:38, 9 April 2007
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	cin >> a[i];		cin >> a[i];
	}		}
	. . .		...
			...
	delete [] a; // When done, free memory pointed to by a.		delete [] a; // When done, free memory pointed to by a.
	a = NULL; // Clear a to prevent using invalid memory reference.		a = NULL; // Clear a to prevent using invalid memory reference.
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	a.push_back(tmp);		a.push_back(tmp);
	\|}		\|}
	a.erase();		...
			...
			a.erase(); // When done, free memory pointed to by a.
	</source>		</source>
	\|}		\|}

Root: /* Good practice in Coding (in C++/C) */

2007-04-09T15:37:03Z

Good practice in Coding (in C++/C)

← Older revision		Revision as of 15:37, 9 April 2007
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	cin >> tmp;		cin >> tmp;
	a.push_back(tmp);		a.push_back(tmp);
	}		\|}
	a.erase();		a.erase();
	</source>		</source>
	\|}		\|}