A Software Approach To Mutual Exclusion Is Lamports Bakery Algorithm

A software approach to mutual exclusion is Lamport’s bakery algorithm [LAMP74], so called because it is based on the practice in bakeries and other shops in which every customer receives a numbered ticket on arrival, allowing each to be served in turn. The algorithm is as follows:
boolean choosing[n];
int number[n];
while (true) {
choosing[i] = true;
number[i] = 1 + getmax(number[], n);
choosing[i] = false;
for (int j = 0; j while (choosing[j]) { };
while ((number[j] != 0) && (number[j],j) }
/* critical section */;
number [i] = 0;
/* remainder */;
The arrays choosing and number are initialized to false and 0, respectively. The ith element of each array may be read and written by process i but only read by other processes. The notation (a, b) (a a. Describe the algorithm in words.
b. Show that this algorithm avoids deadlock.
c. Show that it enforces mutual exclusion.

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