Merge pull request PawanJaiswal08#15 from arihantj13/master

Added Banker's Algorithm

Author: PawanJaiswal08

BANKERS-ALGO.cpp

@@ -0,0 +1,82 @@
+#include<iostream>
+using namespace std;
+  
+const int P = 5;
+
+const int R = 3;
+
+void calculateNeed(int need[P][R], int maxm[P][R],
+                   int allot[P][R])
+{
+    for (int i = 0 ; i < P ; i++)
+        for (int j = 0 ; j < R ; j++)
+            need[i][j] = maxm[i][j] - allot[i][j];
+}
+
+bool isSafe(int processes[], int avail[], int maxm[][R],
+            int allot[][R])
+{
+    int need[P][R];
+    calculateNeed(need, maxm, allot);
+    bool finish[P] = {0};
+    int safeSeq[P];
+    int work[R];
+    for (int i = 0; i < R ; i++)
+        work[i] = avail[i];
+
+    int count = 0;
+    while (count < P)
+    {
+        bool found = false;
+        for (int p = 0; p < P; p++)
+        {
+            if (finish[p] == 0)
+            {
+                int j;
+                for (j = 0; j < R; j++)
+                    if (need[p][j] > work[j])
+                        break;
+                if (j == R)
+                {
+                    for (int k = 0 ; k < R ; k++)
+                        work[k] += allot[p][k];
+                    safeSeq[count++] = p;
+                    finish[p] = 1;
+                    found = true;
+                }
+            }
+        }
+        if (found == false)
+        {
+            cout << "System is not in safe state";
+            return false;
+        }
+    }
+    cout << "System is in safe state.\nSafe"
+         " sequence is: ";
+    for (int i = 0; i < P ; i++)
+        cout << safeSeq[i] << " ";
+  
+    return true;
+}
+int main()
+{
+    int processes[] = {0, 1, 2, 3, 4};
+
+    int avail[] = {3, 3, 2};
+
+    int maxm[][R] = {{7, 5, 3},
+                     {3, 2, 2},
+                     {9, 0, 2},
+                     {2, 2, 2},
+                     {4, 3, 3}};
+
+    int allot[][R] = {{0, 1, 0},
+                      {2, 0, 0},
+                      {3, 0, 2},
+                      {2, 1, 1},
+                      {0, 0, 2}};
+
+    isSafe(processes, avail, maxm, allot);
+    return 0;
+}