Question

Complete 2a-b

2a) Write a C program which displays the sum of the command line
arguments. Hint: use sscanf to convert the decimal arguments
(which are strings) to binary numbers that can be added. Use
the file name sum.c for your program. Test your program with

sum 5 -10 3
and
sum 8
and
sum

2b) Write a C program that reads in a file and outputs it in
reverse order. Use recursion. Test your program with the
file reverse.txt (on our web site). Hint: Structure of
the recursive function reverse that you need:

if not at end of file
read line
save line in a safe area (use strdup to do this)
call reverse
display line that was saved

Use fgets to read line. Recall fgets returns 0 (which represents
false) on end of file.

Answer 1

1)

#include<stdio.h>

int main(int argc,char*argv[])

{

int a,b,sum;

if(argc!=3)

{

printf("please use "prg_name value1,value2\"\n");

return-1;

}

a=atoi(argv[1]);

b=atoi(argv[2]);

sum=a+b;

printf("sum of %d,%d is:%d\n",a,b,sum);

return 0;}

}

}

2)

#include<stdio.h>
#include<conio.h>
long count_characters(FILE *);

void main()

{
int i;

long cnt;

char ch,ch1;

FILE *fp1,fp2;

if(fp1=fopen("file_1.txt,"r"))

{

printf("the file has been opened....\n);

fp2=fopen("file_2.txt","w"):

cnt=count_characters(fp1);

fseek(fp1,-1L,2);

printf("the number of characters to be copied%d\n",ftell(fp1));

while(cnt)

{

ch=fgetc(fp1);

fputc(ch,fp2)

fseek(fp1,=-2l,L,1);

cnt--;

}

printf("\n**file copied successfully in reverseorder**\n");

}

else

{

perror("error occured\n");

}

fclose(fp1);

fopen(fp2);

}

long count_charcteristics(file*f)

{

fseek(f,-1l,2);

long last_pos=ftell(f);

last_pos++;

return last_pos;

}