Checksum Validation

Code

#include <stdio.h>

int validate_checksum(int *mem, int n) {
    // Write your XOR scan logic here
    if(n < 2){
        return 0; // not enough data
    }

    int xor_sum = 0;

    for(int i = 0; i < n - 1; ++i){
        xor_sum ^= mem[i];
    }

    return (xor_sum == mem[n-1]) ? 1 : 0;
}

int main() {
    int n, arr[100];
    scanf("%d", &n);
    
    for (int i = 0; i < n; i++) {
        scanf("%d", &arr[i]);
    }

    int result = validate_checksum(arr, n);
    printf("%d", result);

    return 0;
}

Solving Approach

Questions:
1. Input constraints
    - n >= 2
    - values in mem [0,255]
2. Edge Cases
    - what should the function return if n <2
    - should the function handle negative values or values > 255
3. Function Signature
    - is the function signature fixed?
    - should it print along with returning the value?

Plan:
1. Input validation
2. XOR calculation
3. Checksum comparision
4. Main function

Edge cases:
- n < 2
- all bytes are 0
- large values (input > 255)
- only one data byte