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What is the fastest way to convert int to char* string in C++?
By pulkitjain, history, 4 years ago, In English

Hi All,

I am trying to find the fastest way to convert integer directly to char* (C-string) without converting it to std::string first. I have already tried using std::to_string() function but then also i need to convert it into C-string using c_str() function. Basically an alternative for itoa in c++ for version 11.

Please feel free to give your views regarding this.

Thanks and Regards
Pulkit Jain

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4 years ago, # |
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How about std::to_chars in C++17?

Also, why do you need to convert to char* instead of using std::strings? It seems unnecessary unless you need to squeeze every bit of performance in your code.

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    4 years ago, # ^ |
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    Yes actually, I want to save some nanoseconds. Will to_chars work fine with C++11

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4 years ago, # |
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Auto comment: topic has been updated by pulkitjain (previous revision, new revision, compare).

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4 years ago, # |
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You can use sprintf

char s[10];
int i = 123;
int n = sprintf(s, "%d", i);
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