_Find_next() function in C++ bitset with Examples
The _Find_next() is a built-in function in C++ Biteset class which returns an integer which refers the position of next set bit in bitset after index. If there isn’t any set bit after index, _Find_next(index) will return the size of the bitset.
Syntax:
iterator bitset._Find_next(index) or int bitset._Find_next(index)
Parameters: The function accepts one mandatory parameter index which specifies the index after which the first set bit is to be found in the bitset.
Return Value: The function returns an integer which refers to the position of next set bit in bitset after specified index. If there isn’t any set bit after index(the specified index), _Find_next(index) will return the size of the bitset.
Below is the illustration of the above function:
Example:
// C++ program for illustration // of _Find_next() function #include <bits/stdc++.h> using namespace std; #define M 32 int main() { // default constructor initializes with all bits 0 bitset<M> bset; bitset<M> bset1; bitset<M> bset2; // 00000000000000000000000000100000 bset[5] = 1; // 00000000000000000000010000100000 bset[10] = 1; // 01000000000000100001000000000001 bset1[0] = bset1[12] = bset1[17] = bset1[30] = 1; // function returns the next set bit // in bitset after index 0 cout << "Next set bit after index 0 in bset\n" ; cout << bset._Find_next(0) << "\n" ; // function returns the next set bit // in bitset after index 6 cout << "Next set bit after index 6 in bset\n" ; cout << bset._Find_next(6) << "\n" ; // finds all set bits in bitset bset1 cout << "Find all set bits in bset1\n" ; for ( int i = bset1._Find_first(); i < bset1.size(); i = bset1._Find_next(i)) cout << i << " " ; cout << "\n" ; // function returns bset2.size() // when there isn't any set bit after index cout << "Next set bit after index 5 in bset2\n" ; cout << bset2._Find_next(5) << "\n" ; return 0; } |
Next set bit after index 0 in bset 5 Next set bit after index 6 in bset 10 Find all set bits in bset1 0 12 17 30 Next set bit after index 5 in bset2 32
Reference: https://gcc.gnu.org/onlinedocs/libstdc++/libstdc++-html-USERS-3.4/bitset-source.html