package codility;

/*

* Score 100%

* https://codility.com/demo/results/demoW3GR7Y-TPJ/

*/

class EquilibriumIndex {

public int solution(int[] A) {

if(A.length == 0)

return -1;

else if(A.length ==1)

return 0;

long sum=0;

long bsum[] = new long[A.length];

for(int i=0; i<A.length; i++) {

bsum[i] = sum;

sum +=A[i];

}

for(int i=0; i<A.length; i++) {

long fsum;

if( i<A.length-1) {

fsum = sum-bsum[i]-A[i];

}

else {

fsum = 0;

}

if( fsum == bsum[i] )

return i;

}

return -1;

}

public static void main(String args[]) {

EquilibriumIndex instance = new EquilibriumIndex();

int A[] = {-2147483648};

//int A[] = {2, -1, -2, 1, 500};

//int A[] = {500, 2, -1, -2, 1};

//int A[] = new int[] { -1, 3, -4, 5, 1, -6, 2, 1};

System.err.println(instance.solution(A));

}

}