Thread: C: Find longest series of even and positive numbers

  1. #1
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    C: Find longest series of even and positive numbers

    Hi.

    I need help with this program:

    Example input: 2 4 6 -1 7 3 -2 1
    Output: 3 3 (longest series of even is 3, longest series of positive is 3)

    Here is the code:

    Code:
    #include <stdio.h>
    int even(int x)
     {
    return x % 2 == 0;
     }
    
    int positive(int x)
    {
        return x>0;
    }
    int longest_series(int a[], int n, int (*f) (int)) {
    int i;
    /*Length of the current series is  0 or  1 depending on whether it is a array
    empty or not*/
    int cs = 0;
    /* Longest series is current series */
    int ls = cs;
    for (i = 0; i < n; i++) {
    if ((*f)(a[i]))
    cs++;
    else
    cs = 0;
    if (cs > ls)
    ls = cs;
    }
    return ls;
    }
    int main() {
    int a[] = {2,4,6,-1,7,3,-2,1},
    n = sizeof(a)/sizeof(int);
    printf("%d %d\n", longest_series(a, n, &even),
    longest_series(a, n, &positive));
    return 0;
    }
    My question is how to write this code if the prototype of function is:

    Code:
    void series(int *array, int n, int (*s)(int), int **begining, int *lenght);
    Thanks for replies.

  2. #2
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