C++ Test if map element exists -

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this question has answer here:

i have "array" of strings defined such:

typedef map<int, string> strarr;

whenever this:

strarr args; if(!args[1]) { /*do stuff*/ }

the compiler tells me there's no match 'operator!' why so, , how can fix this?

edit: there way of making work bool operator! ()!

with !args[1], you're trying call operator! on std::string, , indeed, error message right: std::string has no operator!.

to check whether element exists in std::map, use find. return std::map::end if specified key not in map:

if (args.find(1) == args.end()) { ... }

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