It is common to convert an integer (int) to a string (std::string) in C++ programs. Because of the long history of C++ which has several versions with extended libraries and supports almost all C standard library functions, there are many ways to convert an int to string in C++. This post introduces how to convert
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Tag: c++11
How to not use concrete types in lambda function parameters in C++11?
Posted onC++11 requires that lambda function parameters be declared with concrete types. This is sometimes annoying. auto is really nice, especially when the type is complex like std::vector<std::string>::iterator is quite long to type. I know C++14 allows auto in lambda functions. But how to not use concrete types in lambda function parameters in C++11? In C++11,
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How to operator[] access element in a const map in C++?
Posted onHow to operator[] access element in a const map in C++? For example, the compiler will report error on this piece of code: #include <iostream> #include <string> #include <map> std::int64_t count(const std::map<std::string, std::int64_t>& map) { return map[“one”] + map[“two”]; } int main () { std::map<std::string, std::int64_t> map = { {“one”, 1}, {“two”, 2} }; std::cout
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How to make Vim indent C++11 lambdas correctly?
Posted onVim seems not indent C++11 lambas very well. How to make Vim indent C++11 lambdas correctly? For this following program, Vim indents it as #include <iostream> #include <string> #include <vector> #include <algorithm> int main () { std::vector<std::string> strs({“one”, “two”}); std::vector<std::string> newstrs; std::transform(strs.begin(), strs.end(), std::back_inserter(newstrs), [](const std::string& s) -> std::string { if (s == “one”) {
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What’s the standard or common data structure for a list of objects in C++?
Posted onIn C++, what’s the standard or common data structure for a list of objects? In C++, the common data structure for a sequence (“list”) of objects may be std::vector. A vector is a dynamically resizable array. It is “The most extensively used container in the C++ Standard Library …, offering a combination of dynamic memory
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Required packages for building YouCompleteMe for Vim on Fedora 21
Posted onYouCompleteMe for Vim on Fedora 21 reports this error: [zma@laptop:~/.vim/bundle/YouCompleteMe]$ ./install.sh — The C compiler identification is GNU 4.9.2 — The CXX compiler identification is GNU 4.9.2 — Check for working C compiler: /usr/bin/cc — Check for working C compiler: /usr/bin/cc — works — Detecting C compiler ABI info — Detecting C compiler ABI info
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g++: sorry, unimplemented: non-trivial designated initializers not supported
Posted ong++ (version g++ (GCC) 4.8.1 20130603 (Red Hat 4.8.1-1)) report: $ g++ -std=c++11 solution.cpp -o sol solution.cpp: In function ‘int main()’: solution.cpp:50:57: sorry, unimplemented: non-trivial designated initializers not supported Stat init_stat {.depth = 0, .moves = tv, .vec = init}; ^ solution.cpp:50:57: sorry, unimplemented: non-trivial designated initializers not supported solution.cpp:50:57: sorry, unimplemented: non-trivial designated initializers
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4 Ways of Converting String to Int in C++
Posted onIt is common to convert a string (std::string) to integer (int) in C++ programs. Because of the long history of C++ which has several versions with extended libraries and supports almost all C standard library functions, there are many ways to convert a string to int in C++. This post introduces how to convert a
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