Pointers can drive C programmers mad. In fact, I’d say that evidence of this notion is that the most experienced C programmers have an air of insanity about them. To join their club, try working this month’s Exercise.
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\nTo start, consider the following program:<\/p>\n
\r\n#include <stdio.h>\r\n\r\nint main()\r\n{\r\n char *a[] = { \"I\", \"good\", \"language\" };\r\n char *b[] = { \"am\", \"C\", \"excellent\", \"an\" };\r\n char *c[] = { \"a\", \"programmer\", \"very\" };\r\n\r\n printf(\"%s %s %s %s %s %s %s\\n\",\r\n a[0],\r\n b[0],\r\n c[0],\r\n c[2],\r\n a[1],\r\n b[1],\r\n c[1]\r\n );\r\n\r\n return 0;\r\n}<\/pre>\nThree arrays contain various strings. These strings are used in a printf()<\/em> statement, generating this output:<\/p>\nI am a very good C programmer<\/code><\/p>\nThis output is rather easy to guess if you’ve been programming C a while. Just ignore the pointers and use array notation to output the string. But more words are available in the arrays than are output, which hints at this month’s challenge.<\/p>\n
Your goal is to output this string:<\/p>\n
I am an excellent C programmer<\/code><\/p>\nBefore you start coding, you must add another pointer variable, **z<\/code>, declared as follows:<\/p>\nchar **z[] = { a, b, c };<\/code><\/p>\nUsing pointer variable z<\/code> — and only pointer variable z<\/code> — you are to modify the printf()<\/em> statement so that it outputs the string, \"I am an excellent C programmer\"<\/code>.<\/p>\nOnce you figure out how to get the first word out, the rest aren’t as big of an issue. But hopefully this challenge gets your brain to think about pointers and asterisks and parentheses and all of that.<\/p>\n
Click here<\/a> to view my solution.<\/p>\n","protected":false},"excerpt":{"rendered":"Can you handle a double pointer challenge? Continue reading