computer science

Question

Define a structure named Gamer which will have the following elements: Number_of_ favorite_games (int), List_of_favorite_games (2D string). Now declare a structure array of Gamer for 5 gamers and take inputs for them. Now generate a rank list of the games. (Hint: The game which appeared most in the favorite games list will be the top game. In case of tie, print the game which comes alphabetically before)

Answer 1

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include <conio.h>

#define GAME_FILENAME ("E:\\games.dat")

#define GAME_NAME_LENGTH (55)

typedef struct Gamer

{

char ** List_of_favorite_games;

int Number_of_favorite_games;

} _TGamer;

typedef _TGamer* TGamer;

#define GAMER_SIZE (sizeof(_TGamer))

typedef struct _TGameFrequency

{

int freq;

int iIndexPos;

} * TGameFrequency;

#define GAME_FREQ_SIZE (sizeof(struct _TGameFrequency))

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

{

TGameFrequency gameFreqRecPtr1 = (TGameFrequency)rec1;

TGameFrequency gameFreqRecPtr2 = (TGameFrequency)rec2;

int iReturn = gameFreqRecPtr1->freq - gameFreqRecPtr2->freq;

if (iReturn==0)

{

iReturn = gameFreqRecPtr1->iIndexPos-gameFreqRecPtr2->iIndexPos;

}

return(iReturn);

}

//reads game list from file

void ReadGameFile(TGamer gameList)

{

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

int N,iLoop;

char buff[55];

if (fptr!=NULL)

{

fscanf(fptr,"%d",&gameList->Number_of_favorite_games);

N = gameList->Number_of_favorite_games;

fgets(buff,55,fptr); //eats the newline

gameList->List_of_favorite_games = (char**)malloc(N*sizeof(char*));

for (iLoop=0; iLoop<N; iLoop++)

{

gameList->List_of_favorite_games[iLoop]=(char*)malloc(GAME_NAME_LENGTH);

fgets(gameList->List_of_favorite_games[iLoop],GAME_NAME_LENGTH,fptr);

int strLen = strlen(gameList->List_of_favorite_games[iLoop]);

gameList->List_of_favorite_games[iLoop][strLen-1]=0; //replaces the new line with null

printf(" incoming game >%s< \n",gameList->List_of_favorite_games[iLoop]);

}

fclose(fptr);

}

else

{

gameList->Number_of_favorite_games=-1;

}

}

//frees the memory

void GameList_Destroy(TGamer gameList)

{

int iLoop;

for (iLoop=0; iLoop<gameList->Number_of_favorite_games; iLoop++)

{

if (gameList->List_of_favorite_games[iLoop]!=NULL)

{

free(gameList->List_of_favorite_games[iLoop]);

}

}

free(gameList->List_of_favorite_games);

gameList->Number_of_favorite_games=0;

}

//returns the ZER0 based index of the game selected by the user

int GameList_Menu(TGamer gameList)

{

int iLoop;

int gameNum=-1;

int N = gameList->Number_of_favorite_games;

while (gameNum<0 || gameNum>N)

{

for (iLoop=0; iLoop<N; iLoop++)

{

printf(" %d %s \n",(iLoop+1),gameList->List_of_favorite_games[iLoop]);

if ((iLoop+1)%30==0) { printf("\n press key for more games... "); getch(); printf("\n"); }

}

printf(" Input your selection :>");

scanf("%d",&gameNum);

}

return(gameNum-1);

}

int AskAnother()

{

int iReturn=-1;

while (iReturn!=0 && iReturn!=1)

{

printf(" Would you like another game??? 1=YES 0=NO ");

scanf("%d",&iReturn);

}

return(iReturn);

}

//creates subset "favoriteGames" of the gameList, per user selection; updates the frequencies

void BuildGameList(TGamer gameList,TGamer favoriteGames,int * gameFreq)

{

int gameNum;

int iIndexPos=0;

int iLoop;

int done_flag=0;

favoriteGames->Number_of_favorite_games=0;

//gets # of games in the game list and clears the boolean flags to "unmarked";

int N = gameList->Number_of_favorite_games;

int * boolFlags = (int*)malloc(N*sizeof(int));

memset(boolFlags,0,N*sizeof(int));

printf(" # of games in gamelist = %d \n",N);

do

{

gameNum = GameList_Menu(gameList);

boolFlags[gameNum]=1;

favoriteGames->Number_of_favorite_games++;

done_flag = (AskAnother()==0);

}

while (done_flag==0);

favoriteGames->List_of_favorite_games = (char**)malloc(favoriteGames->Number_of_favorite_games*sizeof(char*));

iIndexPos=0;

for (iLoop=0; iLoop<N; iLoop++)

{

if (boolFlags[iLoop])

{

favoriteGames->List_of_favorite_games[iIndexPos] = (char*)malloc(GAME_NAME_LENGTH);

strcpy(favoriteGames->List_of_favorite_games[iIndexPos],gameList->List_of_favorite_games[iLoop]);

iIndexPos++;

gameFreq[iLoop]++;

}

}

free(boolFlags);

}

int MainMenu()

{

int iReturn=-1;

while (iReturn<0 || iReturn>2)

{

printf("**********************************************\n");

printf(" <1> INPUT ANOTHER SURVEY BALLOT \n");

printf(" <2> SHOW CURRENT STATS \n");

printf("**********************************************\n");

printf(" Please input your selection or ZER0 to QUIT :>");

scanf("%d",&iReturn);

}

return(iReturn);

}

void GameList_Dump(TGamer gameList, char * strMsg)

{

int iLoop;

if (strMsg!=NULL)

{

printf("********************************************");

printf(strMsg);

printf("\n");

}

printf("********************************************");

for (iLoop=0; iLoop<gameList->Number_of_favorite_games; iLoop++)

{

printf(gameList->List_of_favorite_games[iLoop]);

printf("\n");

}

}

GameFreqReport(TGamer gameList,int * freq, int nMax)

{

int iLoop;

int N = gameList->Number_of_favorite_games;

TGameFrequency gameFreq = (TGameFrequency) malloc(GAME_FREQ_SIZE*N);

for (iLoop=0; iLoop<N; iLoop++)

{

gameFreq[iLoop].iIndexPos=iLoop;

gameFreq[iLoop].freq = freq[iLoop];

}

qsort(gameFreq,N,GAME_FREQ_SIZE,CompareGameFreq);

if (nMax>N) { nMax=N; }

for (iLoop=N-1; iLoop>=nMax; iLoop--)

{

_TGameFrequency curGameFreqRec = gameFreq[iLoop];

printf(" %s %d \n",gameList->List_of_favorite_games[curGameFreqRec.iIndexPos],curGameFreqRec.freq);

}

}

main()

{

_TGamer gameList;

_TGamer myFavoriteGames;

int iLoop;

//reads the game list from file and intializes the frequencies to zero

ReadGameFile(&gameList);

int * gameFreq = (int*)malloc(gameList.Number_of_favorite_games*sizeof(int));

memset(gameFreq,0,gameList.Number_of_favorite_games*sizeof(int));

int iMenuChoice=-1;

while (iMenuChoice!=0)

{

iMenuChoice = MainMenu();

switch (iMenuChoice)

{

case 1:

{

BuildGameList(&gameList,&myFavoriteGames,gameFreq);

GameList_Dump(&myFavoriteGames,(char*)"GAMES SELECTED");

GameList_Destroy(&myFavoriteGames);

break;

}

case 2:

{

GameFreqReport(&gameList,gameFreq,20);

break;

}

case 0:

{

break;

}

} //switch

} //while

free(gameFreq);

GameList_Destroy(&myFavoriteGames);

GameList_Destroy(&gameList);

}

> cat Games.dat

5

Berzerk

Crazy Climber

Froger

Jungle King

Tron