C / C ++ commonly used functions and their corresponding header files

In the process of brushing questions, there are often some very useful functions that forget his operations and header files. In order to avoid this situation, close up this record:

1. Universal header file #include <bits / stdc ++. H>;

2. Header algorithm: sort, fill;

3. The header file cmath: absolute value function: integer abs, floating point fabs;

4. Header file cctype: islower, isupper, isdight, isalpha, tolower, toupper;

5. The header file string: reverse (str.begin (), str.end ()) (super easy to use), sort (str.begin (), str.end ()) (sorted within the string according to lexicographic order);

6. Header file cstring: memset;

7. Header file sstream: stringstream;

Indefinitely updated. .