Driver Code
public static void main ( String args [ ] ) { GFG g = new GFG ( ) ; String input = "2 ▁ * ▁ pi ▁ + ▁ 3 ▁ * ▁ pi ▁ = ▁ 5 ▁ * ▁ pi " ; System . out . println ( g . replacePi ( input ) ) ; } }