Range-based for loop with strings

This is post just for myself as a memo.

I am confused when I wrote range-based for loop, directly putting string as a target.
Putting string as the target of range-based for loop flashed into my mind when I practiced hashmap like:

int cnt = 0; bool flag = true; while(flag){ for(char &e: "balloon"){ map[e]--; if(map[e] < 0) flag = false; } if(flag) cnt++; } 

However, this while loop finished after the 'n'.
I had no idea about this phenomenon.
This is why, I tested and tried to confirm their movement.

int main(void){ // Your code here! for(auto e: "TestStrings"){ cout << e << ':'; printf("%X ", e); } cout << endl; string s = "TestStrings"; for(auto &e: s){ cout << e << ':'; printf("%X ", e); } } 

This code shows:

// T:54 e:65 s:73 t:74 S:53 t:74 r:72 i:69 n:6E g:67 s:73 :0 // T:54 e:65 s:73 t:74 S:53 t:74 r:72 i:69 n:6E g:67 s:73 

Conclusion: The former has a NULL at its end of the line.