COMPX201-IntSet/Set.java at main · LittleVigney/COMPX201-IntSet · GitHub

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
public class Set{
    int _size;
    int[] intArray;

    public Set(int size) {
        this._size = size;
        intArray = new int[_size];
    }

    public void displaySet(){
        for (int i = 0; i < _size; i++) {
            if (intArray[i] != 0) System.out.print(intArray[i] + " ");
        }
        System.out.println();
    }

    public boolean isEmpty(){
        boolean empty = true;
        for (int i = 0; i < _size; i++) {
            if (intArray[i] > 0){
                empty = false;
                break;
            }
        }
        return empty;
    }

    public boolean hasElement(int goal){
        boolean hasele = false;
        for (int i = 0; i < _size; i++){
            if (intArray[i] == goal){
                hasele = true;
                break;
            }
        }
        return hasele;
    }

    public int add(int goal){
        int addIndex = -1;
        if (this.hasElement(goal)){
            //System.out.println("This integers has been in set.");
            return addIndex;
        }

        // If goal is not in set, add it into location which is 0
        for (int i = 0; i < _size; i++) {
            if (intArray[i] == 0) {
                intArray[i] = goal;
                addIndex = i;
                break;
            }
        }

        return addIndex;
    }

    public void removeItem(int n){
        if(isEmpty()){
            return;
        }
        if(!hasElement(n)){
            return;
        }
        for(int i= 0; i< intArray.length; i++){
            if(intArray[i] == n){
                for(int j = i; j < intArray.length - 1; j++){
                    intArray[j] = intArray[j+1];
                }
                intArray[intArray.length-1] = 0;
                return;
            }
        }
    }

    public boolean isSubset(Set goal){
        if (goal.isEmpty()) return true;
        for (int i = 0; i < goal._size; i++){
            if (!hasElement(goal.intArray[i])){
                return false;
            }
        }
        return true;
    }

    public boolean isEqual(Set goal){
        if (this.isEmpty() && goal.isEmpty()){
            return true;
        }
        if (this.isSubset(goal) && goal.isSubset(this)){
            return true;
        }

        return false;
    }

    public Set union(Set goal){
        Set new_set = new Set(this._size + goal._size);

        if (this.isEmpty() && goal.isEmpty()) return new_set;
        else if (this.isEmpty() && !goal.isEmpty()) new_set = goal;
        else if (!this.isEmpty() && goal.isEmpty()) new_set = this;
        else{
            for (int i = 0; i < this._size; i++){
                if (!new_set.hasElement(this.intArray[i])) new_set.add(this.intArray[i]);
            }
            for (int i = 0; i < goal._size; i++){
                if (!new_set.hasElement(goal.intArray[i])) new_set.add(goal.intArray[i]);
            }
        }

        return new_set;
    }

    public Set intersection(Set goal){
        Set new_set = new Set(this._size + goal._size);

        for (int i = 0; i < this._size; i++){
            if (goal.hasElement(this.intArray[i])){
                new_set.add(this.intArray[i]);
            }
        }

        return new_set;
    }

    public Set difference(Set goal){
        Set new_set = new Set(this._size + goal._size);

        for (int i = 0; i < this._size; i++){
            if (!goal.hasElement(this.intArray[i])) new_set.add(this.intArray[i]);
        }

        return new_set;
    }

    public Set symmetricDifference(Set goal){
        return this.union(goal).difference(this.intersection(goal));
    }
}