In Progress Medium

In a laboratory, there are various chemicals, and each chemical is represented by a symbol such as H$,$ B$,$ C$,$ O$,$ F$,$ etc. A student has added chemicals to a jar one by one. He wants to know the chermical mixture that he created using the chemicals.

Given a string of chemical symbols that represent the order in which the student added the chemicals to the jar. Write a program to print a string with each chemical symbolalong with the number of times it is added continuously. Join different chemical symbols using the plus $1+1$ as shown in the sample output.

If a chemical is added only once without any repetition, print the chemical name without its count.

Ex: "HHCOO" $"$H$2+$C$+$O$2"$