Equilibrium index of an array | Java program to find equilibrium index of an array ; function to find the equilibrium index ; Check for indexes one by one until an equilibrium index is found ; get left sum ; get right sum ; if leftsum and rightsum are same , then we are done ; return - 1 if no equilibrium index is found ; Driver code
class EquilibriumIndex { int equilibrium ( int arr [ ] , int n ) { int i , j ; int leftsum , rightsum ; for ( i = 0 ; i < n ; ++ i ) { leftsum = 0 ; rightsum = 0 ; for ( j = 0 ; j < i ; j ++ ) leftsum += arr [ j ] ; for ( j = i + 1 ; j < n ; j ++ ) rightsum += arr [ j ] ; if ( leftsum == rightsum ) return i ; } return - 1 ; } public static void main ( String [ ] args ) { EquilibriumIndex equi = new EquilibriumIndex ( ) ; int arr [ ] = { - 7 , 1 , 5 , 2 , - 4 , 3 , 0 } ; int arr_size = arr . length ; System . out . println ( equi . equilibrium ( arr , arr_size ) ) ; } }