Answer:
check out the solution.
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1.
CODE:
#include<stdio.h>
#include<string.h>
int main(int argc, char *argv[]) {
// variable declaration
char str[100];
int i;
// infinite while loop
while(1)
{
// prompt user to enter input
printf("\nEnter the Input (9999 to quit) : ");
// reads the input from console
scanf("%[^\n]%*c",str);
if(strcmp(str, "9999") == 0) // EOF - indicates end of user input
break;
// check for the command line argument
if(strcmp(argv[1], "--upper") == 0)
{
// loop through characters and convert accordingly
for (i = 0; i < strlen(str); i++)
{
if(str[i] >= 'a' && str[i] <= 'z' && str[i] != ' ')
{
str[i] = str[i] - 32;
}
}
// display the converted string
printf("%s", str);
}
else if(strcmp(argv[1], "--lower") == 0)
{
for (i = 0; i < strlen(str); i++)
{
if(str[i] >= 'A' && str[i] <= 'Z' && str[i] != ' ')
str[i] = str[i] + 32;
}
printf("%s", str);
}
else if(strcmp(argv[1], "--swap") == 0)
{
for (i = 0; i < strlen(str); i++)
{
if(str[i] >= 'A' && str[i] <= 'Z' && str[i] != ' ')
str[i] = str[i] + 32;
else if(str[i] >= 'a' && str[i] <= 'z' && str[i] != ' ')
str[i] = str[i] - 32;
}
printf("%s", str);
}
else // print the message appropriately if invalid argument
printf("\n\nInvalid command line argument!!!");
// if-elseif ends
} // infinite while loop ends
} // main ends
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OUTPUT :
1. command line argument : --upper
2. command line argument : --lower
3. command line argument : --swap
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2.
CODE:
#include<stdio.h>
#include<string.h>
int main(int argc, char *argv[]) {
// variable declaration
char str[100];
int i, cnt = 0;
// infinite while loop
while(1)
{
// prompt user to enter input
printf("\nEnter the Input (9999 to quit) : ");
// reads the input from console
scanf("%[^\n]%*c",str);
if(strcmp(str, "9999") == 0) // EOF - indicates end of user input
break;
// loop through characters and convert accordingly
for (i = 0; i < strlen(str); i++)
{
// check if char is in between 0 and 9 and count them if any
if(str[i] >= '0' && str[i] <= '9')
{
cnt++;
}
}
} // infinite while loop ends
// when input reaches EOF - display the count of digits
printf("%d digits", cnt);
} // main ends
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OUTPUT :
1.
2.
3.
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