Note: This answer applies to the C language, not C++. Null Pointers The integer constant literal 0 has different meanings depending upon the context in which it’s used. In all cases, it is still an integer constant with the value 0, it is just described in different ways. If a pointer is being compared to … Read more
No, you can’t. The compiler doesn’t know what the pointer is pointing to. There are tricks, like ending the array with a known out-of-band value and then counting the size up until that value, but that’s not using sizeof(). Another trick is the one mentioned by Zan, which is to stash the size somewhere. For … Read more
Where are MIN and MAX defined in C, if at all? They aren’t. What is the best way to implement these, as generically and type safe as possible (compiler extensions/builtins for mainstream compilers preferred). As functions. I wouldn’t use macros like #define MIN(X, Y) (((X) < (Y)) ? (X) : (Y)), especially if you plan … Read more
You have pointers and values: int* p; // variable p is pointer to integer type int i; // integer value You turn a pointer into a value with *: int i2 = *p; // integer i2 is assigned with integer value that pointer p is pointing to You turn a value into a pointer with … Read more
The number 7709179928849219.0 has the following binary representation as a 64-bit double: 01000011 00111011 01100011 01110101 01010011 00101011 00101011 01000011 +^^^^^^^ ^^^^—- ——– ——– ——– ——– ——– ——– + shows the position of the sign; ^ of the exponent, and – of the mantissa (i.e. the value without the exponent). Since the representation uses binary … Read more
printf(“%05d”, zipCode); The 0 indicates what you are padding with and the 5 shows the width of the integer number. Example 1: If you use “%02d” (useful for dates) this would only pad zeros for numbers in the ones column. E.g., 06 instead of 6. Example 2: “%03d” would pad 2 zeros for one number … Read more
All the other answers are correct, but just for completion A function is declared in the following manner: return-type function-name(parameter-list,…) { body… } return-type is the variable type that the function returns. This can not be an array type or a function type. If not given, then int is assumed. function-name is the name of … Read more
As others have said, the issue is the store to the memory location in the array: x[i][j]. Here’s a bit of insight why: You have a 2-dimensional array, but memory in the computer is inherently 1-dimensional. So while you imagine your array like this: 0,0 | 0,1 | 0,2 | 0,3 —-+—–+—–+—- 1,0 | 1,1 … Read more
Warning! This is a list of random books of diverse quality. In the view of some people (with some justification), it is no longer a list of recommended books. Some of the listed books contain blatantly incorrect statements or teach wrong/harmful practices. People who are aware of such books can edit this answer to help … Read more
Type info variables to list “All global and static variable names” (huge list. Type info locals to list “Local variables of current stack frame” (names and values), including static variables in that function. Type info args to list “Arguments of the current stack frame” (names and values).