How to map array elements with all their indexes where they repeat

#1

https://ide.codingblocks.com/s/270156. try to create map<int,vector> but it gives error

#2

@rohitkandpal683 the way you are doing traversal of the map is wrong. i will give you a key-value PAIR. pair.first will give you the key(int) and pair.second wil give you the value (vector)
i have made changes, it is running now https://ide.codingblocks.com/s/270164

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