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How to make my custom type to work with “range-based for loops”?

...ample of why this is useful is that your end iterator can read "check your char* to see if it points to '0'" when == with a char*. This allows a C++ range-for expression to generate optimal code when iterating over a null-terminated char* buffer. struct null_sentinal_t { template<class Rhs, ...
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How to determine CPU and memory consumption from inside a process?

...hysMemUsedByMe = pmc.WorkingSetSize; CPU currently used: #include "TCHAR.h" #include "pdh.h" static PDH_HQUERY cpuQuery; static PDH_HCOUNTER cpuTotal; void init(){ PdhOpenQuery(NULL, NULL, &cpuQuery); // You can also use L"\\Processor(*)\\% Processor Time" and get individual CPU...
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Binary Data in JSON String. Something better than Base64

... so that it can be placed into a string element (i.e. zero or more Unicode chars in double quotes using backslash escapes) in JSON. ...
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How can you make a custom keyboard in Android?

...) { case Keyboard.KEYCODE_DELETE: CharSequence selectedText = ic.getSelectedText(0); if (TextUtils.isEmpty(selectedText)) { // no selection, so delete previous character ic.deleteSurroundingText(1, 0); ...
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Is std::vector so much slower than plain arrays?

... created. What happens if we change Pixel to: struct Pixel { unsigned char r, g, b; }; Result: about 10% faster. Still slower than an array. Hm. # ./vector UseArray completed in 3.239 seconds UseVector completed in 5.567 seconds Idea #4 - Use iterator instead of loop index How about usin...
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Is it possible to print a variable's type in standard C++?

...f typename std::remove_reference<T>::type TR; std::unique_ptr<char, void(*)(void*)> own ( #ifndef _MSC_VER abi::__cxa_demangle(typeid(TR).name(), nullptr, nullptr, nullptr), #else nullptr, #endif ...
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How do pointer to pointers work in C?

...his case, if this is the only occurrence of "hello" in memory then, const char *c = "hello"; ... defines c to be a pointer to the (read-only) string "hello", and thus contains the value 63. c must itself be stored somewhere: in the example above at location 58. Of course we can not only point to ...
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How to concatenate a std::string and an int?

...tm; sstm << name << age; result = sstm.str(); // 7. with itoa char numstr[21]; // enough to hold all numbers up to 64-bits result = name + itoa(age, numstr, 10); // 8. with sprintf char numstr[21]; // enough to hold all numbers up to 64-bits sprintf(numstr, "%d", age); result = name + ...
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C libcurl get output into a string

... #include <string.h> #include <curl/curl.h> struct string { char *ptr; size_t len; }; void init_string(struct string *s) { s->len = 0; s->ptr = malloc(s->len+1); if (s->ptr == NULL) { fprintf(stderr, "malloc() failed\n"); exit(EXIT_FAILURE); } s->pt...
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warning: implicit declaration of function

...er has not seen the declaration. */ return 0; } int fun(int x, char *p) { /* ... */ } You need to declare your function before main, like this, either directly or in a header: int fun(int x, char *p); sha...