In C++, std::substr() is a predefined function used for string handling. string.h is the header file required for string functions.
This function takes two values pos and len as an argument and returns a newly constructed string object with its value initialized to a copy of a sub-string of this object. Copying of string start from pos and done till pos+len means [pos, pos+len).
- The index of the first character is 0 (not 1).
- If pos is equal to the string length, the function returns an empty string.
- If pos is greater than the string length, it throws out_of_range. If this happen, there are no changes in the string.
- If for the requested sub-string len is greater than size of string, then returned sub-string is [pos, size()).
string substr (size_t pos, size_t len) const; Parameters: pos: Position of the first character to be copied. len: Length of the sub-string. size_t: It is an unsigned integral type. Return value: It returns a string object.
String is: eek
- How to get sub-string after a character?
In this a string and a character is given and you have to print the sub-string followed by the given character.
Extract everything after the “:” in the string “dog:cat”.
// CPP program to illustrate substr()
// Take any string
string s =
// Find position of ':' using find()
pos = s.find(
// Copy substring after pos
string sub = s.substr(pos + 1);
// prints the result
"String is: "
String is: cat
- Print all substrings of a given string
- Sum of all substrings of a string representing a number
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