bitset

问题 This question already has an answer here : Why does a large local array crash my program, but a global one doesn't? [duplicate] (1 answer) Closed 2 years ago . When I write the following program, it works correctly i.e. the bitset array is declared outside the main() method. Correctly Works #include <iostream> #include <bitset> using namespace std; bitset<5000> set[5000]; int main(){ cout<<"program runs fine"<<endl; return 0; } But I get stack-overflow exception when I create it inside the

问题 This question already has an answer here : Why does a large local array crash my program, but a global one doesn't? [duplicate] (1 answer) Closed 2 years ago . When I write the following program, it works correctly i.e. the bitset array is declared outside the main() method. Correctly Works #include <iostream> #include <bitset> using namespace std; bitset<5000> set[5000]; int main(){ cout<<"program runs fine"<<endl; return 0; } But I get stack-overflow exception when I create it inside the

问题 This question already has an answer here : Why does a large local array crash my program, but a global one doesn't? [duplicate] (1 answer) Closed 2 years ago . When I write the following program, it works correctly i.e. the bitset array is declared outside the main() method. Correctly Works #include <iostream> #include <bitset> using namespace std; bitset<5000> set[5000]; int main(){ cout<<"program runs fine"<<endl; return 0; } But I get stack-overflow exception when I create it inside the

问题 This question already has an answer here : Why does a large local array crash my program, but a global one doesn't? [duplicate] (1 answer) Closed 2 years ago . When I write the following program, it works correctly i.e. the bitset array is declared outside the main() method. Correctly Works #include <iostream> #include <bitset> using namespace std; bitset<5000> set[5000]; int main(){ cout<<"program runs fine"<<endl; return 0; } But I get stack-overflow exception when I create it inside the

问题 Comparing the following two expressions std::bitset<8>(5).count() __builtin_popcount(5) which one is better? 回答1: int __builtin_popcount(unsigned int); is a built in function of GCC while std::bitset<N>::count is a C++ standard. Both function do the same thing: return the number of bits that are set to true . What should you use? Always tend to use C++ standard's functions because other compilers don't support __builtin_popcount function. UPDATE If you take a look at the statistics made by

问题 Comparing the following two expressions std::bitset<8>(5).count() __builtin_popcount(5) which one is better? 回答1: int __builtin_popcount(unsigned int); is a built in function of GCC while std::bitset<N>::count is a C++ standard. Both function do the same thing: return the number of bits that are set to true . What should you use? Always tend to use C++ standard's functions because other compilers don't support __builtin_popcount function. UPDATE If you take a look at the statistics made by

问题 I get a segmentation fault when I try to run the code below. I've tried commenting out bits of the code, and found that the while loop with the condition j < is_prime.size() is the culprit. This is puzzling to me because I perform the same check between the same values in the for loop above it, but do not get a segmentation fault. Could someone explain to me what's the issue here? I'm using GCC 4.8.2 on Linux 64. #include <bitset> #include <iostream> using namespace std; const size_t max

问题 I get a segmentation fault when I try to run the code below. I've tried commenting out bits of the code, and found that the while loop with the condition j < is_prime.size() is the culprit. This is puzzling to me because I perform the same check between the same values in the for loop above it, but do not get a segmentation fault. Could someone explain to me what's the issue here? I'm using GCC 4.8.2 on Linux 64. #include <bitset> #include <iostream> using namespace std; const size_t max

问题 In my application i'm trying to display the bit representation of double variables. It works for smaller double variables. Not working for 10^30 level. Code: #include <iostream> #include <bitset> #include <limits> #include <string.h> using namespace std; void Display(double doubleValue) { bitset<sizeof(double) * 8> b(doubleValue); cout << "Value : " << doubleValue << endl; cout << "BitSet : " << b.to_string() << endl; } int main() { Display(1000000000.0); Display(2000000000.0); Display

问题 I have a std::bitset but now I want to use an STL algorithm on it. I could have used std::vector<bool> instead, but I like std::bitset 's constructor and I want std::bitset 's bitwise operations. Do I have to go through a loop and stuff everything in a std::vector<bool> to use STL algorithms, and then copy that back to the std::bitset , or is there a better way? 回答1: If you do not want to write loops using the operator[] of the bitset , then you might try using bitset::to_string() to convert