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41932b5 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 | Write the method
void removeNegatives(ArrayList<Integer> numnbers)
...which removes all numbers less than zero from the list.
Tip: the for loop may not work reliably if the iterated structure changes during loop execution
- you should use another way to iterate through the list instead.
Example method call:
public static void main(String[] parameters){
ArrayList<Integer> numbers = new ArrayList<>();
numbers.add(1);
numbers.add(-2);
numbers.add(-5);
numbers.add(10);
System.out.println(numbers);
removeNegatives(numbers);
System.out.println(numbers);
}
Program outputs:
[1, -2, -5, 10]
[1, 10]
============================
import java.util.Random;
import java.util.ArrayList;
public class Test{
public static void main(String[] args){
final Random r = new Random();
int[][] s = {{1,-2,3}, {10,-20,30,-40}, {-2,4,-6,8,-10}, {-9,-1,-8,2,7,3,-6,-4}};
for (int[] pa : s) {
ArrayList<Integer> lista = new ArrayList<>();
for (int l : pa) lista.add(l);
System.out.println("List before: ");
System.out.println("" + lista);
System.out.println("List after: ");
removeNegatives(lista);
System.out.println(lista);
System.out.println("");
}
}
// ADD
public static void removeNegatives(ArrayList<Integer> numbers) {
for (int i = 0; i < numbers.size(); i++) {
if (numbers.get(i) < 0) {
numbers.remove(i);
// because we remove the current idx
// adjust i by 1 (like as if we finished the previous 'i')
// System.out.println(i);
i--;
// System.out.println(i);
}
}
}
}
// Test1
// List before:
// [1, -2, 3]
// List after:
// 1
// 0
// [1, 3]
// List before:
// [10, -20, 30, -40]
// List after:
// 1
// 0
// 2
// 1
// [10, 30]
// List before:
// [-2, 4, -6, 8, -10]
// List after:
// 0
// -1
// 1
// 0
// 2
// 1
// [4, 8]
// List before:
// [-9, -1, -8, 2, 7, 3, -6, -4]
// List after:
// 0
// -1
// 0
// -1
// 0
// -1
// 3
// 2
// 3
// 2
// [2, 7, 3]
List before:
[1, -2, 3]
List after:
[1, 3]
List before:
[10, -20, 30, -40]
List after:
[10, 30]
List before:
[-2, 4, -6, 8, -10]
List after:
[4, 8]
List before:
[-9, -1, -8, 2, 7, 3, -6, -4]
List after:
[2, 7, 3]
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