Greedy Algorithm - Shortest Job First (SJF) CPU Scheduling

// Input list of process execution times
const input = [4, 3, 7, 1, 2];

// Function to calculate the average waiting time using SJF
function averageWaitingTimeSJF(processTimes) {
    // Sort the process times in ascending order
    const sortedTimes = processTimes.slice().sort((a, b) => a - b);

    let totalWaitingTime = 0;
    let accumulatedTime = 0;

    // Calculate total waiting time
    for (let i = 0; i < sortedTimes.length - 1; i++) {
        accumulatedTime += sortedTimes[i];
        totalWaitingTime += accumulatedTime;
    }

    // Calculate average waiting time
    const averageWaitingTime = totalWaitingTime / sortedTimes.length;
    return averageWaitingTime;
}

// Get the average waiting time
const avgWaitingTime = averageWaitingTimeSJF(input);

console.log('Average Waiting Time:', avgWaitingTime);
// output 4

Time Complexity: O(n) + nlogn (Sort+ Iteration)
Space Complexity: O(1) (Just tampering the data)

Thank you for reading!