Given an array A of N positive numbers. The task is to find the position where equilibrium first occurs in the array. Equilibrium position in an array is a position such that the sum of elements before it is equal to the sum of elements after it. Input: The first line of input contains an integer T, denoting the number of test cases. Then T test…

equilibrium.dart

void main() {
  
List a=[1,4,5,2,2];
  int sum=0;
  int leftSum=0;
  for(int v in a)
    sum+=v;

  for(int i=0;i<a.length;i++){
    sum-=a[i];
    if(sum==leftSum){
      print(a[i]);
      return;
    }
    leftSum+=a[i];
  }
  print('-1');
}