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Looping through a Nested C Map of Maps
To iterate over a nested map in C , where the map contains a map of strings to strings, you can utilize the ranged-based for loop syntax. Here's an updated solution for C 11 and beyond:
std::map<std::string, std::map<std::string, std::string>> mymap; for (const auto &[outer_key, inner_map] : mymap) { // Outer key is accessible via 'outer_key' for (const auto &[inner_key, inner_value] : inner_map) { // Inner key is accessible via 'inner_key' // Inner value is accessible via 'inner_value' } }
This approach eliminates unnecessary copies and provides a concise and elegant way to access the keys and values in the nested map.
For C 17, you can simplify this even further using structured bindings:
for (const auto &[outer_key, inner_map] : mymap) { for (const auto &[inner_key, inner_value] : inner_map) { // Access your 'outer_key', 'inner_key', and 'inner_value' directly } }
This technique allows you to directly access the variables without having to define intermediate references like ent1, ent2, and so on.
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