Problem with WHILE loop.

This is a discussion on Problem with WHILE loop. within the C Programming forums, part of the General Programming Boards category; Code: while(grade[i] != -1) { printf("GRADE: ");scanf("%f",&grade[i]); i++;count++; } I don't get a compilation error, but if I enter in ...

  1. #1
    Registered User kinghajj's Avatar
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    Problem with WHILE loop.

    Code:
    while(grade[i] != -1)
    {
    		printf("GRADE: ");scanf("%f",&grade[i]);
    		i++;count++;
    }
    I don't get a compilation error, but if I enter in -1 as a number the program just continues to ask for the grade over and over again.

  2. #2
    End Of Line Hammer's Avatar
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    Is grade an array of floats or ints?

    As you've incremented i, the test within the while won't be looking at the number you've just entered.
    When all else fails, read the instructions.
    If you're posting code, use code tags: [code] /* insert code here */ [/code]

  3. #3
    Been here, done that.
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    Re: Problem with WHILE loop.

    Originally posted by kinghajj
    Code:
    while(grade[ i ] != -1)
    {
    		printf("GRADE: ");scanf("%f",&grade[ i ]);
    		i++;count++;
    }
    I don't get a compilation error, but if I enter in -1 as a number the program just continues to ask for the grade over and over again.
    You are reading a value into grade[ i ], you then increment i past the read in value, and compare the wrong grade (which is zero)
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  4. #4
    End Of Line Hammer's Avatar
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    >>and compare the wrong grade (which is zero)
    Where'd you get the idea it's zero? More than likely it's undefined (at least, that's my guess).
    When all else fails, read the instructions.
    If you're posting code, use code tags: [code] /* insert code here */ [/code]

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