Computer Science - Raptor Programming - Sorting Problem

Question

Given the text file grades.txt containing student names, their school names and marks respectively, use Raptor to develop an algorithm to sort the marks in decreasing values. Note the format of the grades.txt (Attached) where the name of a student is immediately followed, in the next two lines, by the name of their school and their mark respectively. The sorted marks shall be written to a file called sortedgrades.txt. For the example data given in grades.txt, the content of the sortedgrades.txt must be stored in the format shown below:

John Bolton: ITM : 71

Jan Chen : ITM : 85

Mohamed SaLazar : SBM : 87

Meriam Sandburg : HTM : 67

Mat Simms : HTM : 72

Navdeep Bahn : ITM : 88

Mary Eastman : ENT : 74

Answer 1

using namespace std;

#include <iostream>

#include <stdlib.h>

#include <stdio.h>

#include <string.h>

typedef struct _TGradeRec

{

char firstname[55];

char lastname[55];

char school[55];

int grade;

} * TGradeRec;

#define GRADE_REC_SIZE (sizeof(struct _TGradeRec))

#define GRADES_INPUT_FILENAME ("grades.txt")

#define GRADES_OUTPUT_FILENAME ("sortedgrades.txt")

void SerializeGradeRec( TGradeRec gradeRec, char * delimBuff)

{

sprintf(delimBuff,"%s %s:%s:%d\n",gradeRec->firstname,gradeRec->lastname,gradeRec->school,gradeRec->grade);

}

void OutputGradeRec(TGradeRec gradeRec, char * debugMsg)

{

if (debugMsg!=NULL)

{

cout << "******************************************************" << endl;

cout << debugMsg << endl;

}

cout << "******************************************************" << endl;

cout << " first name =>" << gradeRec->firstname << "<" << endl;

cout << " last name =>" << gradeRec->lastname << "<" << endl;

cout << " school =>" << gradeRec->school << "<" << endl;

cout << " grade = " << gradeRec->grade << endl;

}

void ParseGradeRec(TGradeRec gradeRec, char * delimBuff)

{

char token[255];

char nameStr[255];

strcpy(nameStr,strtok(delimBuff,":"));

strcpy(gradeRec->school,strtok(NULL,":"));

strcpy(token,strtok(NULL,":"));

gradeRec->grade = atoi(token);

strcpy(gradeRec->firstname,strtok(nameStr," "));

strcpy(gradeRec->lastname,strtok(NULL," "));

OutputGradeRec(gradeRec,(char*)"parsed grade rec");

}

int CompareGradeRec ( const void * rec1, const void * rec2)

{

TGradeRec gradeRec1 = (TGradeRec) rec1;

TGradeRec gradeRec2 = (TGradeRec) rec2;

return (

( gradeRec1->grade) - (gradeRec2->grade)

);

}

int GetGradeCount()

{

char inbuff[255];

int iReturn=0;

FILE * fptr = fopen(GRADES_INPUT_FILENAME,"r");

if (fptr!=NULL)

{

while (

fgets(inbuff,255,fptr)!=NULL

)

{

cout << "read " << inbuff;

iReturn++;

}

fclose(fptr);

}

return(iReturn);

}

int InputGrades(TGradeRec grades, int numGradeRecs)

{

int iReturn=-1;

FILE * fptr = fopen(GRADES_INPUT_FILENAME,"r");

char inbuff[255];

if (fptr!=NULL)

{

for (int iLoop=0; iLoop<numGradeRecs; iLoop++)

{

fgets(inbuff,255,fptr);

ParseGradeRec(&grades[iLoop],inbuff);

}

fclose(fptr);

iReturn=0;

}

return(iReturn);

}

void OutputGrades(TGradeRec grades, int n)

{

FILE * fptr = fopen(GRADES_OUTPUT_FILENAME,"w+");

for (int iLoop=0; iLoop<n; iLoop++)

{

char outbuff[255];

SerializeGradeRec(&grades[iLoop],outbuff);

fputs(outbuff,fptr);

}

fclose(fptr);

}

int main()

{

int numGrades = GetGradeCount();

cout << "\n # of grade records = " << numGrades << endl;

TGradeRec grades = (TGradeRec) malloc( numGrades*GRADE_REC_SIZE);

int iReturn = InputGrades(grades,numGrades);

if (iReturn==0)

{

qsort(grades,numGrades,GRADE_REC_SIZE,CompareGradeRec);

OutputGrades(grades,numGrades);

}

if (grades!=NULL) { free(grades); }

}