updates to articles

OS/C/Week5/q2.c

@@ -22,11 +22,17 @@ void main () {
 
 	// input
 	printf("Enter strings to print: \n");
+	const size_t str_size = 100;
 	for (i = 0; i < 5; i++) {
-		strings[i] = malloc (100 * sizeof(char));
-		string_cpy[i] = malloc (100 * sizeof(char));
-		fgets(strings[i],100,stdin);
-		strcpy(string_cpy[i], strings[i]);
+		strings[i] = malloc(str_size);
+		string_cpy[i] = malloc(str_size);
+		if (!strings[i] || !string_cpy[i]) {
+			fprintf(stderr, "Memory allocation failed\n");
+			exit(1);
+		}
+		if (fgets(strings[i], str_size, stdin)) {
+			memcpy(string_cpy[i], strings[i], str_size);
+		}
 	}
 
 	// forking
@@ -68,5 +74,3 @@ void main () {
 	}
 
 }
-
-

OS/C/Week5/q2_opt.c

@@ -0,0 +1,76 @@
+// stdlib import
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+// bash utilities import
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+void main () {
+
+	// array declaration
+	char *strings[5];
+	char *string_cpy[5];
+	char temp[100];
+
+	// variables reqd
+	int i,j;
+	pid_t pid;
+	int status;
+
+	// input
+	printf("Enter strings to print: \n");
+	const size_t str_size = 100;
+	for (i = 0; i < 5; i++) {
+		strings[i] = malloc(str_size);
+		string_cpy[i] = malloc(str_size);
+		if (!strings[i] || !string_cpy[i]) {
+			fprintf(stderr, "Memory allocation failed\n");
+			exit(1);
+		}
+		if (fgets(strings[i], str_size, stdin)) {
+			memcpy(string_cpy[i], strings[i], str_size);
+		}
+	}
+
+	// forking
+	pid = fork();
+
+	// child process
+	if (pid == 0) {
+		printf("\n Child Process: \n");
+		for (i = 0; i < 5; i++) {
+			for (j = 0; j < 5 - i - 1; j++) {
+				if (strcmp(strings[j], strings[j + 1]) > 0){
+					strcpy(temp, strings[j]);
+					strcpy(strings[j], strings[j+1]);
+					strcpy(strings[j+1], temp);
+				}
+			}
+		}
+
+
+		for (i = 0; i < 5; i++) {
+			printf("\n Child: %s \n", strings[i]);
+		}
+
+		printf("\n");
+		exit (00);
+
+	// parent process
+	} else if (pid > 0) {
+		wait(&status);
+		printf("\n Parent Process: \n");
+		for (i = 0; i < 5; i++) {
+			printf("\n Parent: %s \n", string_cpy[i]);
+			printf("%d",WEXITSTATUS(status));
+		}
+
+	// exception handling (catchall statement)
+	} else {
+		printf("THE SYSTEM ENCOUNTERED AN ERROR. Please try again later or debug the code. \n");
+	}
+
+}

OS/C/Week5/q2opt.c

@@ -0,0 +1,27 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+int compare_strings(const void *a, const void *b) {
+    return strcmp(*(const char **)a, *(const char **)b);
+}
+
+int main(int argc, char *argv[]) {
+    pid_t pid = fork();
+    if (pid == 0) {
+        qsort(&argv[1], argc - 1, sizeof(char *), compare_strings);
+        printf("Child Sorted:\n");
+        for (int i = 1; i < argc; ++i)
+            printf("%s\n", argv[i]);
+        exit(EXIT_SUCCESS);
+    } else {
+        wait(NULL);
+        printf("\nParent Unsorted:\n");
+        for (int i = 1; i < argc; ++i)
+            printf("%s\n", argv[i]);
+    }
+    return 0;
+}

OS/C/Week5/q3opt.c

@@ -0,0 +1,93 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+int compare_strings(const void *a, const void *b) {
+    return strcmp(*(const char **)a, *(const char **)b);
+}
+
+void bubble_sort_strings(char **arr, int n) {
+    for (int i = 0; i < n - 1; ++i)
+        for (int j = 0; j < n - i - 1; ++j)
+            if (strcmp(arr[j], arr[j + 1]) > 0) {
+                char *temp = arr[j]; arr[j] = arr[j + 1]; arr[j + 1] = temp;
+            }
+}
+
+int partition(char **arr, int low, int high) {
+    char *pivot = arr[high];
+    int i = (low - 1);
+    for (int j = low; j <= high - 1; ++j)
+        if (strcmp(arr[j], pivot) < 0) {
+            i++;
+            char *temp = arr[i]; arr[i] = arr[j]; arr[j] = temp;
+        }
+    char *temp = arr[i + 1]; arr[i + 1] = arr[high]; arr[high] = temp;
+    return (i + 1);
+}
+
+void quick_sort_strings(char **arr, int low, int high) {
+    if (low < high) {
+        int pi = partition(arr, low, high);
+        quick_sort_strings(arr, low, pi - 1);
+        quick_sort_strings(arr, pi + 1, high);
+    }
+}
+
+void print_strings(char **strings, int n, const char *process, const char *sort) {
+    printf("\n%s (%s):\n", process, sort);
+    for (int i = 0; i < n; ++i) printf("%s\n", strings[i]);
+}
+
+char **read_strings(int n) {
+    char **strings = malloc(n * sizeof(char *));
+    for (int i = 0; i < n; ++i) {
+        size_t size = 100;
+        strings[i] = malloc(size);
+        printf("String %d: ", i + 1);
+        getline(&strings[i], &size, stdin);
+        strings[i][strcspn(strings[i], "\n")] = 0; // Remove newline
+    }
+    return strings;
+}
+
+int main() {
+    int n;
+    printf("N strings: ");
+    scanf("%d", &n);
+    while (getchar() != '\n');
+    char **input = read_strings(n);
+
+    pid_t pid_bubble = fork();
+    if (pid_bubble == 0) {
+        char **sorted_bubble = malloc(n * sizeof(char *));
+        for (int i = 0; i < n; ++i) sorted_bubble[i] = strdup(input[i]);
+        bubble_sort_strings(sorted_bubble, n);
+        print_strings(sorted_bubble, n, "Child BubbleSort", "Bubble Sort");
+        for (int i = 0; i < n; ++i) free(sorted_bubble[i]);
+        free(sorted_bubble);
+        exit(0);
+    }
+
+    pid_t pid_quick = fork();
+    if (pid_quick == 0) {
+        char **sorted_quick = malloc(n * sizeof(char *));
+        for (int i = 0; i < n; ++i) sorted_quick[i] = strdup(input[i]);
+        quick_sort_strings(sorted_quick, 0, n - 1);
+        print_strings(sorted_quick, n, "Child QuickSort", "Quick Sort");
+        for (int i = 0; i < n; ++i) free(sorted_quick[i]);
+        free(sorted_quick);
+        exit(0);
+    }
+
+    wait(NULL);
+    printf("\nParent (Unsorted):\n");
+    for (int i = 0; i < n; ++i) printf("%s\n", input[i]);
+
+    for (int i = 0; i < n; ++i) free(input[i]);
+    free(input);
+    return 0;
+}

OS/bash/Week2/12h.c

@@ -0,0 +1 @@
+30   │     find . -type f -name '*[0-9]*' -exec wc {} +xy

OS/bash/Week2/ITStudents.txt

@@ -0,0 +1,10 @@
+1001:Rahul:CSE:AI:A:78:82:90
+1002:Priya:ICT:Information Technology:B:88:79:85
+1003:Anil:ELE:ECE:A:75:80:70
+1004:Sunita:CSE:CSE:C:90:92:88
+1005:Vikram:ICT:CCE:D:65:70:75
+1006:Anita:ELE:EEE:A:80:85:90
+1007:Ravi:CSE:AI:B:70:68:74
+1008:Meena:ICT:Information Technology:A:92:88:95
+1009:Suresh:ELE:ECE:B:55:60:65
+1010:Kavita:CSE:CSE:A:85:90:87

OS/bash/Week2/answers.md

@@ -21,7 +21,7 @@ Q3.
 
 Q4.	
 ```bash
-	grep -rl "MIT" . | xargs sed -i 's/MIT/Manipal Institute of Technology/g'
+	grep "MIT" * | sed 's/MIT/Manipal Institute of Technology/g'
 ```
 
 Q5.	
@@ -38,4 +38,4 @@ Q6.
 
 ```bash
 	pkill wc
-```
+```

OS/bash/Week2/college.txt

@@ -0,0 +1,2 @@
+IIT
+MIT

OS/bash/Week2/manipals.txt

@@ -0,0 +1,2 @@
+MIT Bangalore
+MIT Manipal

OS/bash/Week2/studentinformation.txt

@@ -0,0 +1,11 @@
+RegistrationNo:Name:Department:Branch:Section:Sub1:Sub2:Sub3
+1001:Rahul:CSE:AI:A:78:82:90
+1002:Priya:ICT:IT:B:88:79:85
+1003:Anil:ELE:ECE:A:75:80:70
+1004:Sunita:CSE:CSE:C:90:92:88
+1005:Vikram:ICT:CCE:D:65:70:75
+1006:Anita:ELE:EEE:A:80:85:90
+1007:Ravi:CSE:AI:B:70:68:74
+1008:Meena:ICT:IT:A:92:88:95
+1009:Suresh:ELE:ECE:B:55:60:65
+1010:Kavita:CSE:CSE:A:85:90:87