GPIO Pin Toggle

Question

Problem: GPIO Pin Toggle. Solve this hands-on electronics task on EWskills.

Accepted Answer

#include 
using namespace std;

// Inline function that toggles a pin state
inline int togglePin(int currentState) {
    return currentState == 0 ? 1 : 0;
}

int main() {
    int state[10];

    for (int i = 0; i < 10; i++) {
        cin >> state[i];
    }

    int n;
    cin >> n;

    for (int i = 0; i < n; i++) {
        int pin;
        cin >> pin;
        state[pin] = togglePin(state[pin]);
    }

    for (int i = 0; i < 10; i++) {
        cout << state[i];
        if (i < 9) cout << " ";
    }

    return 0;
}

Explanation & Logic Summary:

The inline function performs a simple state inversion.
Each toggle request updates the pin immediately.
Repeated indices cause repeated toggles.
Inline functions reduce call overhead in tight loops.

Firmware Relevance & Real-World Context:

GPIO toggling is fundamental in embedded systems (LEDs, diagnostics, timing).
Inline functions are commonly used in HAL and driver layers.
Reinforces safe array indexing assumptions typical in MCU firmware.
Represents simplified behavior of memory-mapped GPIO registers.

22. GPIO Pin Toggle