Adding marks to student list

in the line where student_map[s1] = 100; in which part of the structure are we adding the marks?

@S19LPPP0015 100 would not be stored in the structure, it stored in the unordered_map, here the key will be s1 and associated value will be 100. We cannot get this value from structure, we will need to use map only to access this associated value.
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