Program to store family members details in C++:
#include
#include
#include
struct record
{
char name[30];
int age;
char state[40];
}x;
//calculates average of ages all family members
float averagecalculation(char sr_file[20])
{
float avg;
int totalmembers=0,totalage=0;
FILE *fp1;
fp1=fopen(sr_file,"r");
if(fp1==NULL)
{
printf("cannot read file %s",sr_file);
exit(0);
}
while(fscanf(fp1,"%[^\n]%d%[^\n]",&x.name,&x.age,&x.state)!=EOF)
{
totalmembers++;
totalage=totalage+x.age;
}
fclose(fp1);
avg=(float)totalage/totalmembers;
return avg;
}
//prints family members names who live in TEXAS
void print_members_of_texas(char sr_file[20])
{
FILE *fp1;
fp1=fopen(sr_file,"r");
if(fp1==NULL)
{
printf("cannot read file %s",sr_file);
exit(0);
}
printf("\nFamily members who live in Texas are\n");
while(fscanf(fp1,"%[^\n]%d%[^\n]",&x.name,&x.age,&x.state)!=EOF)
{
if(strcmp(x.state,"TEXAS")==0)
printf("\n%s",x.name);
}
fclose(fp1);
}
void main()
{
FILE* fp1;
char sr_file[20];
float avg;
clrscr();
printf("Enter the source file name to enter data");
gets(sr_file);
fp1=fopen(sr_file,"w");
if(fp1==NULL)
{
printf("cannot create %s ",sr_file);
exit(0);
}
while(1)
{
fflush(stdin);
printf("Enter name of ur family member(-1 to quit) ");
scanf("%[^\n]",x.name);
if(strcmp(x.name,"-1")==0)
break;
fflush(stdin);
printf("Enter his age ");
scanf("%d",&x.age);
if (x.age<1)
{
printf("invalid input ");
continue;
}
fflush(stdin);
printf("Enter state where he lives ");
scanf("%[^\n]",x.state);
fprintf(fp1,"%s\t%d\t%s\n",x.name,x.age,x.state);
}
fclose(fp1);
printf("Done reading input");
//Now calculate average
avg=averagecalculation(sr_file);
printf("\nAverage age of family is %f ",avg);
//Now check if any family member is in Texas
print_members_of_texas(sr_file);
getch();
}
PROGRAM Description
Program has 3 functions.
1.Main()- creates a file to store family members details .It opens the file in write mode. Its fields are name of member ,age and where he lives. Then it takes input into the structure record fields called name ,age ,state till user presses -1. It checks if age entered is >1 or not ,otherwise it gives "invalid input"Then it completes taking input by closing the file. After that it calls 2 functions named averagecalculation() and print_members_of_texas() for calculating the average of family members age and to print the family members who live in TEXAS respectively.
2.averagecalculation()- It is a function to calculate the average of all family members. It is started by opening the file created in main function in read mode. It reads each record of file stored in sequence till end of file. It calculates average of ages. Lastly closes the file and returns to main() with average.
3.print_members_of_texas()-It is started by opening the file created in main function in read mode. It reads each record of file stored in sequence till end of file. Then it check each record if person's city is TEXAS or not, if it is so this function prints the person's name. Lastly closes the file.