Compilation Error : Due to hashmap.replace method

Main.java:37: cannot find symbol
symbol : method replace(int,int)
location: interface java.util.Map<java.lang.Integer,java.lang.Integer>
m.replace(a[i], ++count);
^
Note: Main.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
1 error

Please help me. below is the link of solution submitted…
http://www.codechef.com/viewsolution/4523853

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