Find Top 3 Largest Values in an Array

Code

#include <stdio.h>
#include <stdint.h>

void find_top_3(uint8_t *arr, uint8_t n) {
    // Simple selection sort for top 3
    for (uint8_t i = 0; i < 3 && i < n; i++) {
        uint8_t max_idx = i;
        for (uint8_t j = i + 1; j < n; j++) {
            if (arr[j] > arr[max_idx]) {
                max_idx = j;
            }
        }
        // Swap arr[i] and arr[max_idx]
        uint8_t temp = arr[i];
        arr[i] = arr[max_idx];
        arr[max_idx] = temp;
    }

    // Print top 3 elements
    for (uint8_t i = 0; i < 3 && i < n; i++) {
        printf("%hhu", arr[i]);
        if (i < 2 && i < n - 1) {
            printf(" ");
        }
    }
}

int main() {
    uint8_t n;
    scanf("%hhu", &n);
    uint8_t arr[100];

    for (uint8_t i = 0; i < n; i++) {
        scanf("%hhu", &arr[i]);
    }

    find_top_3(arr, n);
    return 0;
}

Solving Approach

• Partial Selection Sort:
  • Loop i from 0 to 2 (or n-1 if n < 3)
  • In each pass, find the maximum element from i to n-1 and swap it to position i
• Print the first 3 elements, which are now the top 3 largest values in descending order