หาค่ามากเป็นอันดับสอง

#include <limits.h>
#include <stdio.h>
int main(void) {
    int values[] = {7, 23, 12, 23, 9}, first = INT_MIN, second = INT_MIN;
    // Maintain the two largest distinct values.
    for (int i = 0; i < 5; ++i) { int value = values[i]; if (value > first) { second = first; first = value; } else if (value > second && value != first) second = value; }
    printf("second=%d\n", second);
}

#include <iostream>
#include <limits>
#include <vector>
int main() {
    std::vector values{7, 23, 12, 23, 9}; int first = std::numeric_limits<int>::min(), second = first;
    // Maintain the two largest distinct values.
    for (int value : values) { if (value > first) { second = first; first = value; } else if (value > second && value != first) second = value; }
    std::cout << "second=" << second << '\n';
}