My Java solution using just arrays. It passed all test cases

public class Solution {

public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    int n1 = in.nextInt();
    int n2 = in.nextInt();
    int n3 = in.nextInt();
    int[] numberOfCylinders = {n1, n2, n3};
    int[][] stack = {new int[n1], new int[n2], new int[n3]};
    int[] height = {0, 0, 0}; 
    for (int i = 0; i < 3; i++) {
        for (int j = 0; j < numberOfCylinders[i]; j++) {
            int cylinderHeight = in.nextInt();
            stack[i][j] = cylinderHeight;
            height[i] += cylinderHeight;
        }   
    }
    int[] index = {0, 0, 0};
    int targetHeight = Math.min(Math.min(height[0], height[1]), height[2]);
    while (height[0] != height[1] || height[1] != height[2]) {
        for (int i = 0; i < 3; i++) {
            if (height[i] > targetHeight) {
                height[i] -= stack[i][index[i]++]; 
                targetHeight = Math.min(targetHeight, height[i]);
            }
        }
    }
    System.out.println(targetHeight);
}  

}