Check to see if a array is a rainbow array

[fiery knoll]

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[desert elm]

You forgot to post some code.

[hybrid crown]

none of my code works... that's why i didn't post

[desert elm]

If your code worked you wouldn't need to ask for help. If you ask for help with code that doesn't work, how do you suggest we find the problem if there's nothing to look at?

[hybrid crown]

ok let me post one

#include <stdbool.h>

bool isRainbowArray(int arr[], int n) {
    int i = 0;
    int j = n - 1;
    
    // Check if the array has an odd number of elements
    if (n % 2 == 0) {
        return false;
    }
    
    // Check if the first half is in strictly increasing order
    for (i = 0; i < n/2; i++) {
        if (arr[i] != i + 1) {
            return false;
        }
    }
    
    // Check if the second half is in strictly decreasing order
    for (j = n - 1; j >= n/2; j--) {
        if (arr[j] != n - j) {
            return false;
        }
    }
    
    // Check if the maximum element is 7 and it contains all the digits from 1 to 7
    int count[8] = {0};
    for (i = 0; i < n; i++) {
        count[arr[i]]++;
    }
    for (i = 1; i <= 7; i++) {
        if (count[i] != 1) {
            return false;
        }
    }
    
    return true;
}

int main() {
    int t, n, i, j;
    
    scanf("%d", &t);
    
    for (i = 1; i <= t; i++) {
        scanf("%d", &n);
        
        int arr[n];
        for (j = 0; j < n; j++) {
            scanf("%d", &arr[j]);
        }
        
        if (isRainbowArray(arr, n)) {
            printf("yes\n");
        } else {
            printf("no\n");
        }
    }
    
    return 0;
}```

also i was unable to integrate all of the mandatory test cases

i just can't understand where to use them

[desert elm]

Hmm, what specific part doesn't behave as it should?

[hybrid crown]

i was hoping u could help on that part

[desert elm]

I can't see any report on which test cases fail

[hybrid crown]

here u go

[sleek mulch]

There are quite a few issues with your code

What happens, if there is let's say number 9 somewhere?

Or, a case:
112345676543221

It passes your checks

[hybrid crown]

umm but i did write a for loop for that int count[8] = {0}; for (i = 0; i < n; i++) { count[arr[i]]++; } for (i = 1; i <= 7; i++) { if (count[i] != 1) { return false; } }

[sleek mulch]

Why is count supposed to be 1? How do you handle numbers bigger than 7? You just access array out of bounds, which is UB

[hybrid crown]

well i was not sure just a hunch.

that me and my friend came up with