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arrayscfor-loopintegercomparison

how can I make a loop print out missing elements in my int array?


I've been trying to solve an assignment where you:

  1. Enter the size N of an array of ints
  2. Enter the max value M of the ints that you want to populate the array with
  3. Enter N values that are of a value between 1 and M, into a second array.
  4. compare these two and print out the missing numbers...

Like this:

Size of array? 10        // => N = 10
Max value in array? 8    // => M = 8

Please enter 10 values between 1 and 8:
4 1 3 1 7 3 4 4 6 1

Missing values: 2 5 8

for some reason, my for loop just prints out all the numbers between 1 and M instead, no matter what I try... What am I missing??

code:

#include <stdio.h>

int main(void)
{
    int aSize, mValue;



    printf("Size of array? ");
    scanf(" %d", &aSize);
    printf("Max value in array: ");
    scanf(" %d", &mValue);

    int table[aSize];
    int values[mValue];

    for (int i = 0; i < aSize; i++)
    {
        table[i] = i+1;
        if ((i+1) > mValue)
        {
            table[i] = 0;
        }
    }

    printf("Please enter %d values between 1 and %d:\n", aSize, mValue);

    for (int i = 0; i < mValue; i++)
    {
        scanf(" %d", &values[i]);
    }

    for(int i = 0; i < aSize; i++)
    {
        for (int j = 0; j < mValue; j++)
        {
            if(table[i] != values[j] && table[i] != 0)
            {
                printf("%d ", table[i]);
                break;
            }
        }
    }
}

Solution

  • #include <stdio.h>
       int main()
       {
        int aSize, mValue;
        printf("Size of array? ");
        scanf(" %d", &aSize);
        printf("Max value in array: ");
        scanf(" %d", &mValue);
    
        int table[aSize];
        int values[aSize]; // not 'mSize' because it is just max value not size of array
    
        for (int i = 0; i < aSize; i++)
        {
            table[i] = i+1;
            if ((i+1) > mValue)
            {
                table[i] = 0;
            }
        }
    
        printf("Please enter %d values between 1 and %d:\n", aSize, mValue);
    
        for (int i = 0; i < aSize; i++)
        {
            scanf(" %d", &values[i]);
        }
    
        for(int i = 0; i < aSize; i++)
        {
            int flag=0;
            for (int j = 0; j < aSize; j++)
            {
                if(table[i] == 0 || table[i] == values[j]) // numbers in common or zero
                {
                    flag=1;
                    break;
                }
            }
            if(flag == 0) printf("%d",table[i]); // missing numbers
        }
    }