C language programming exercise reference answer Chapter 8 Document (2)

/* 8.8retrieve the score from the file ex88_1.txt. Sort the score and store the score in the descending order */
# Include "stdio. H"
# Define N 10
Struct student
{
Int num;
Char name [20];
Int score [3];/* float cannot be used */
Float average;
};

Void sort (struct student STU []);
Void print (File * FP, struct student STU []);
Void printtopfive (File * FP, struct student STU []);

void main ()
{< br> struct student s [N];
int I;
file * FP1, * fp2;
char ch;
If (FP1 = fopen ("C: \ ex88_1.txt", "R") = NULL)
{< br> printf ("file c: \ ex88_1.txt" cannot be opened);
exit (1 );
}< br> If (fp2 = fopen ("C: \ ex88_2.txt", "W") = NULL)
{< br> printf ("file c: \ ex88_2.txt" cannot be opened);
exit (1);
}

for (I = 0; I {< br> fscanf (FP1, "% d % S % d", & S [I]. num, s [I]. name, & S [I]. score [0],
& S [I]. score [1], & S [I]. score [2]);
S [I]. average = (s [I]. score [0] + s [I]. score [1] + s [I]. score [2])/3.0;
}< br> fprintf (fp2, "Original Score report \ n");
Print (fp2, S );
sort (s);
fprintf (fp2, "sorted score report \ n");
Print (fp2, S );
fprintf (fp2, "Top Five score reports \ n");
printtopfive (fp2, S);
}

Void sort (struct student STU [])
{
Int I, K, J;
Struct Student t;
For (I = 0; I <N-1; I ++)
{
K = I;
For (j = I + 1; j <n; j ++)
{
If (STU [K]. Average <STU [J]. Average)
K = J;
If (K! = I)
{
T = STU [I];
STU [I] = STU [k];
STU [k] = T;
}
}

}
}

Void print (File * FP, struct student STU [])
{
Int I;
Fprintf (FP, "studentid studentname score1 score2 score3 average \ n ");
For (I = 0; I <n; I ++)
Fprintf (FP, "%-10D %-12 S % 8d % 8d % 8d % 8.1f \ n", STU [I]. Num, STU [I]. Name,
STU [I]. Score [0], STU [I]. Score [1], STU [I]. Score [2], STU [I]. Average );
}

Void printtopfive (File * FP, struct student STU [])
{
Int I;
Fprintf (FP, "studentname average \ n ");
For (I = 0; I <5; I ++)
Fprintf (FP, "%-12 S % 8.1f \ n", STU [I]. Name, STU [I]. Average );
}

/* Obtain the score from ex88_1.txt?

20001 name (1) 70 80 90
20002 name (2) 71 81 91
20003 name (3) 72 82 92
20004 name (4) 73 83 93
20005 name (5) 74 84 94
20006 name (6) 75 85 95
20007 name (7) 76 86 96
20008 name (8) 77 87 97
20009 name (9) 78 88 98
20010 name (10) 79 89 99
*/

/* After sorting, store ex88_2.txt in descending order

Original Score report
Studentid studentname score1 score2 score3 average
20001 name (1) 70 80 90 80.0
20002 name (2) 71 81 91 81.0
20003 name (3) 72 82 92 82.0
20004 name (4) 73 83 93 83.0
20005 name (5) 74 84 94 84.0
20006 name (6) 75 85 95 85.0
20007 name (7) 76 86 96 86.0
20008 name (8) 77 87 97 87.0
20009 name (9) 78 88 98 88.0
20010 name (10) 79 89 99 89.0
Sorted score report
Studentid studentname score1 score2 score3 average
20010 name (10) 79 89 99 89.0
20009 name (9) 78 88 98 88.0
20008 name (8) 77 87 97 87.0
20007 name (7) 76 86 96 86.0
20006 name (6) 75 85 95 85.0
20005 name (5) 74 84 94 84.0

*/