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Computer Programming using JavaOne Dimensional Arrays - 07
CHAPTER
7
[] = {, . . . , };
(One Dimensional Arrays)
1. (Introduction to Arrays)
1. 1)
(Arrays) ""
2)
(Index) -0 (Zero Index) ()
3)
4)
n
2.
1. Initialized List Initialized List
i nt a[ ] = {34, 56, 52, 12, 90, 0, 75, 23, 45, 8}; 0 1 2 3 4 5 6 7 8 9
34 56 52 12 90 0 75 23 45 8
6 1 7 9'C'
'U'
1
6 1 7 9
0 1 2 3
(Index) 0 (Order) 1
6 1 7 9 4 (4 )0 1 2 3
6 1 2 1
7 09 4
5 3
[ ]
Comma
10 9
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Computer Programming using Java 07 - One Dimensional Arrays
=new [];
[ ] = new [ ] ;
[ ] = new [ ] ;
[]0 1 2 3 4 5 6 7 8 9
a[0] a[1] a[2] a[3] a[4] a[5] a[6] a[7] a[8] a[9]
1 [] Error (8 )
0 1 2 3 4 5 6 7 8 9
2. newnew
1)
i nt a[ ] ;
2)
a = new i nt [ 3] ;
3)
4) 1 2 (2 )
a[ 0] a[ 1] a[ 2]
a
12345678910
i nt i = 3;i nt a[ ] = { 0, 2, 4, 6, 8, 1, 3, 5, 7, 9 };Syst em. out . pr i nt l n( a[ 0] + a[ 6] ) ;System. out . pr i nt l n( a[ 1] * - - a[ 4] ) ; System. out . pr i nt l n( a[ 9] ++) ; Syst em. out . pr i nt l n( a[ 10] + a[ 4] ) ;System. out . pr i nt l n( a[ 1] ++ + a[ 0] ) ;Syst em. out . pr i nt l n( a[ 5 + 3] ) ;Syst em. out . pr i nt l n( - - a[ 2*i ] + a[ 1] ++) ;System. out . pr i nt l n( a[ 1] + a[ 4] + a[ 9] ) ;
0 0 0
0 1 2
[];
a
()
[ ]
[ ]
[ ]
0 (i nt )
int a[ ] = new int[3] ;
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Computer Programming using JavaOne Dimensional Arrays - 07
.length
5)
() 1 0
i nt data[ ] = new i nt [ 3 * n + 1] ; ()
doubl e a[ ] = new doubl e[ 5] ; 5 0.0
3. . l engt h
. l engt h( )
2 [] (12 )1) num 15 200 (2 )
2) dice (2 )
3) avgGrade451 (2 )
4) grade2110101 369 (2 )
5) x 10 (2 )
6)
merge
1
2 (2
)
123456
i nt a[ ] = new i nt [ 5] ;Syst em. out . pr i nt l n( a. l engt h) ;St r i ng s = " J AVA! " ;System. out . pr i nt l n( s. l engt h( ) ) ;i nt b[ ] = new i nt [ 12] ;System. out . pr i nt l n( b. l engt h( ) ) ;
l engt h
l engt h
Error
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Computer Programming using Java 07 - One Dimensional Arrays
= [ ] ;
[ ] = ;
4. 1)
i nt n = num[ 0] ; (nnum0)
2)
num[ 0] = 13; (num0 13)
3) f or (0) (length - 1)
3 [] (12 )
1)
x num50 (2 )
2) y num50 (2 )
3) c code(2 )
4)
12 bank var1(2 )boolean var1 = 5 > 6;
5)1 bank var2(2 )double var2 = kb.nextDouble();
6)bank var3(2 )char var3 = "java".charAt(3);
1234
i nt a[ ] = new i nt [ 5] ;fo r ( int i = 0; i < a.length; i ++) {
a[ i ] = 100;}
a.length
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Computer Programming using JavaOne Dimensional Arrays - 07
4 [] (55 )1)
nInitialed List 1 20 n (5 )
2) m 1000 m 1-1000 m(5 )
3) a 100 (5 )Scanner kb = new Scanner(System.in);
4)
x(10 )int x[] = { 7, 9, -1, 4, 12, 9, 3, 2, -7, 2, 1, 9, -15, 24, 11, 13 };
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Computer Programming using Java 07 - One Dimensional Arrays
5) xnumx(10 )int num[] = { 3, 2, 1, 10, 2, 8, 3, 2, 1, 1, 8, 5, 10, 11, 7, 6, 10 };
Scanner kb = new Scanner(System.in);
5 [] (Merge) a b ab ab(10 )import java.util.Scanner;
public class MergeArrays {public static void main(String[] args) {
int a[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
int b[] = { 1, 4, 6, 8, 10, 12 };
} //End of main} //End of class
6 [] x(Split) numxupperlower(10 )import java.util.Scanner;
public class SplitArray {
public static void main(String[] args) {
-1
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int num[] = {95, 1, 6, 34, 5, 9, 123, -2, 57, 82, 12, 79, 45, 34, 1};
} //End of main} //End of class
7 [] (Reverse Array) num
(10 )import java.util.Scanner;
public class ReverseArray {
public static void main(String[] args) {int num[] = {95, 1, 6, 34, 5, 9, 123, -2, 57, 82, 12, 79, 45, 34, 1};
} //End of main
} //End of class
8 [] ab (10 )
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import java.util.Scanner;
public class EqualityOfArrays {public static void main(String[] args) {
int a[] = { 1, 2, 3, 4, 5, 6, 7 }, b[] = { 1, 2, 3, 5, 5, 7, 7 };
} //End of main} //End of class
9 []
key
key
num-1 (10 )import java.util.Scanner;
public class LastSecondSearch {public static void main(String[] args) {
int num[] = { 3, 2, 1, 10, 2, 8, 3, 2, 1, 1, 8, 5, 10, 11, 7, 6, 10 };
} //End of main} //End of class
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3. (Applications of Array)
1. (Selection Sort) (10)
fo r i i fo r j i
i
2. (Bubble Sort) (10)
fo r i i fo r j i
i ()
10 [] (Selection Sort)
1 2 (Bubble Sort) -x (20 )int x[] = {30, 45, 23, 2, 19, 14, 5, 99, 9};
30 45 23 2 19 14 5 99 9
1
2
1
2345678
f or ( i nt i = dat a. l engt h - 1; i >= 1; i - - ) {
i nt maxI ndex = 0;f or ( i nt j = 0; j dat a[ maxI ndex] ) maxI ndex = j ;i nt t emp = dat a[ i ] ;dat a[ i ] = dat a[ maxI ndex] ;dat a[ maxI ndex] = t emp;
}
1234567
89
f or ( i nt i = dat a. l engt h - 1; i >= 1; i - - ) {f or ( i nt j = 0; j < i ; j ++) {
i f ( dat a[ j ] > dat a[ j + 1] ) {i nt t emp = dat a[ j ] ;dat a[ j ] = dat a[ j + 1] ;dat a[ j + 1] = t emp;
}
}}
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3
4
5
6
7
8
1
2
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3.
(Binary Search)() (dat a)
11 [] x 14 (10 )
int x[] = {30, 45, 23, 2, 19, 14, 5, 99, 9};
30 45 23 2 19 14 5 99 9
1234567
891011
i nt l ef t = 0, r i ght = dat a. l engt h - 1, mi d = 0;whi l e ( l ef t
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12 [ ] birthdate.txt dd-mm-yyyy 13-06-1987 200 12
(10 )
import java.util.Scanner;import java.io.*;
public class SortMonthByBirthDate {public static void main(String[] args) throws IOException {
} //End of main} //End of class
birthdate.txt
September [ 25 peopl e]March [ 22 peopl e]J anuar y [ 21 peopl e]May [19 peopl e]J une [ 19 peopl e]. . .
13- 02- 200001- 10- 198931- 01- 199921- 12- 199517- 07- 1994. . .
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13 [] How To Be Noob student.txt5 (5%) (10%) (10%) (30%) (45%) student.txt5 (100%) totalscore.txt (85 )
import java.io.*;import java.util.Scanner;
public class ScoreCalculator {
public static void main(String[] args) throws IOException {
//in1 student.txt count(5 )
51310001215331000221
52310003215031000421493100052149310006215231000721. . .
student.txt5131000121 3 7 3 20 265331000221 4 6 9 24 40
5231000321 0 1 8 25 275031000421 0 3 10 15 04931000521 2 0 7 28 254931000621 4 6 7 3 195231000721 2 10 3 27 45. . .
student.txt
5131000121 59 D5331000221 83 A5231000321 61 C5031000421 28 F
4931000521 62 C4931000621 39 F5231000721 87 A5031000821 63 C5131000921 44 F. . .
totalscore.txt. . .Max Score: 87Max Scor e Freq: 1Max Scor e Year : 2
Mi n Scor e: 14Mi n Score Freq: 1Mi n Score Year : 4Avg Scor e: 49. 72Max Fr eq: 5Li st Max Fr eq Scor e: 33 60
totalscore.txt
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//in2 student.txtidid(5 )
//out1 student.txt
5 -(0-5) (0-10) (0-10) (0-30) (0-45)(10 )
//in3 student.txtscsc(10 )
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//out2 totalscore.txt5 A(80-100) B(70-79) C(60-69) D(50-59) F(0-49) (10 )
// (Max Score) (Min Score)// (Max Score Freq) (Min Score Freq) // ()
//(Average Score)// (Max Freq) //(List Max Freq Score) (15 )
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// totalscore.txt(10 )
// (5 )
} //End of main} //End of class