get_long_long - prompts user for a line of text from stdin and returns the equivalent long long

#include <cs50.h>

long long get_long_long(const char *format, ...);

Prompts user for a line of text from standard input and returns the equivalent long long; if the text does not represent a long long or would cause overflow, user is reprompted.

The prompt is formatted like printf(3).

This function will be deprecated in favor of get_long(3).

Returns the long long equivalent to the line read from stdin in [LLONG_MIN, LLONG_MAX). If line can’t be read, returns LLONG_MAX.

/**
 * Returns the difference of two long longs read from stdin, or LLONG_MAX if there was an error.
 */
long long subtract_long_longs(void)
{
    // read long long from stdin
    long long i = get_long_long("Enter a long long: ");

    // make sure we read one successfully
    if (i == LLONG_MAX)
    {
        return LLONG_MAX;
    }

    long long j = get_long_long("What do you want to subtract from %lld? ", i);

    if (j == LLONG_MAX)
    {
        return LLONG_MAX;
    }

    return i - j;
}

get_char(3), get_double(3), get_float(3), get_int(3), get_long(3),
get_string(3), printf(3)