Upload files to "DS/C/Lab/Week6"

DS/C/Lab/Week6/InfixToPrefix.c

@@ -0,0 +1,91 @@
+#include <stdio.h>
+#include <string.h>
+
+#define MAX_SIZE 100
+
+char stack[MAX_SIZE];
+int top = -1;
+
+void push(char item) {
+    if (top >= MAX_SIZE - 1) {
+        printf("Stack Overflow\n");
+        return;
+    }
+    stack[++top] = item;
+}
+
+char pop() {
+    if (top < 0) {
+        printf("Stack Underflow\n");
+        return -1;
+    }
+    return stack[top--];
+}
+
+int precedence(char symbol) {
+    switch (symbol) {
+        case '^': return 3;
+        case '*':
+        case '/': return 2;
+        case '+':
+        case '-': return 1;
+        default: return 0;
+    }
+}
+
+void reverse(char *str) {
+    int len = strlen(str);
+    int i, j;
+    char temp;
+    for (i = 0, j = len - 1; i < j; i++, j--) {
+        temp = str[i];
+        str[i] = str[j];
+        str[j] = temp;
+    }
+}
+
+int isalnum(char c) {
+    return ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z'));
+}
+
+void infixToPrefix(char infix[], char prefix[]) {
+    char symbol, temp[2];
+    int i, j = 0;
+    
+    reverse(infix);
+    
+    for (i = 0; infix[i] != '\0'; i++) {
+        symbol = infix[i];
+        if (isalnum(symbol)) {
+            prefix[j++] = symbol;
+        } else if (symbol == ')') {
+            push(symbol);
+        } else if (symbol == '(') {
+            while ((temp[0] = pop()) != ')') {
+                prefix[j++] = temp[0];
+            }
+        } else {
+            while (top > -1 && precedence(stack[top]) > precedence(symbol)) {
+                prefix[j++] = pop();
+            }
+            push(symbol);
+        }
+    }
+    
+    while (top > -1) {
+        prefix[j++] = pop();
+    }
+    prefix[j] = '\0';
+    
+    reverse(prefix);
+}
+
+int main() {
+    char infix[MAX_SIZE], prefix[MAX_SIZE];
+    printf("Enter infix expression: ");
+    fgets(infix, MAX_SIZE, stdin);
+    infix[strcspn(infix, "\n")] = 0;  // Remove newline if present
+    infixToPrefix(infix, prefix);
+    printf("Prefix expression: %s\n", prefix);
+    return 0;
+}

DS/C/Lab/Week6/PrefixCheck.c

@@ -0,0 +1,70 @@
+#include <stdio.h>
+#include <string.h>
+
+#define MAX_SIZE 100
+
+int stack[MAX_SIZE];
+int top = -1;
+
+void push(int item) {
+    if (top >= MAX_SIZE - 1) {
+        printf("Stack Overflow\n");
+        return;
+    }
+    stack[++top] = item;
+}
+
+int pop() {
+    if (top < 0) {
+        printf("Stack Underflow\n");
+        return -1;
+    }
+    return stack[top--];
+}
+
+int isOperator(char c) {
+    return (c == '+' || c == '-' || c == '*' || c == '/');
+}
+
+int isDigit(char c) {
+    return (c >= '0' && c <= '9');
+}
+
+int evaluatePrefix(char* expr) {
+    int len = strlen(expr);
+    for (int i = len - 1; i >= 0; i--) {
+        if (isDigit(expr[i])) {
+            push(expr[i] - '0');
+        } else if (isOperator(expr[i])) {
+            int operand1 = pop();
+            int operand2 = pop();
+            switch (expr[i]) {
+                case '+': push(operand1 + operand2); break;
+                case '-': push(operand1 - operand2); break;
+                case '*': push(operand1 * operand2); break;
+                case '/': 
+                    if (operand2 != 0) push(operand1 / operand2);
+                    else {
+                        printf("Error: Division by zero\n");
+                        return -1;
+                    }
+                    break;
+            }
+        }
+    }
+    return pop();
+}
+
+int main() {
+    char expr[MAX_SIZE];
+    printf("Enter prefix expression: ");
+    fgets(expr, MAX_SIZE, stdin);
+    expr[strcspn(expr, "\n")] = 0;  // Remove newline if present
+    
+    int result = evaluatePrefix(expr);
+    if (result != -1) {
+        printf("Result: %d\n", result);
+    }
+    
+    return 0;
+}

DS/C/Lab/Week6/PrefixToInfix.c

@@ -0,0 +1,63 @@
+#include <stdio.h>
+#include <string.h>
+
+#define MAX_SIZE 100
+
+char stack[MAX_SIZE][MAX_SIZE];
+int top = -1;
+
+void push(const char* item) {
+    if (top >= MAX_SIZE - 1) {
+        printf("Stack Overflow\n");
+        return;
+    }
+    strcpy(stack[++top], item);
+}
+
+char* pop() {
+    if (top < 0) {
+        printf("Stack Underflow\n");
+        return NULL;
+    }
+    return stack[top--];
+}
+
+int isOperator(char c) {
+    return (c == '+' || c == '-' || c == '*' || c == '/');
+}
+
+int isAlphanumeric(char c) {
+    return ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z'));
+}
+
+void prefixToInfix(char* prefix) {
+    int len = strlen(prefix);
+    char temp[MAX_SIZE];
+    
+    for (int i = len - 1; i >= 0; i--) {
+        if (isAlphanumeric(prefix[i])) {
+            temp[0] = prefix[i];
+            temp[1] = '\0';
+            push(temp);
+        } else if (isOperator(prefix[i])) {
+            char op1[MAX_SIZE], op2[MAX_SIZE], result[MAX_SIZE];
+            strcpy(op1, pop());
+            strcpy(op2, pop());
+            sprintf(result, "(%s%c%s)", op1, prefix[i], op2);
+            push(result);
+        }
+    }
+    
+    printf("Infix expression: %s\n", stack[top]);
+}
+
+int main() {
+    char prefix[MAX_SIZE];
+    printf("Enter prefix expression: ");
+    fgets(prefix, MAX_SIZE, stdin);
+    prefix[strcspn(prefix, "\n")] = 0;  // Remove newline if present
+    
+    prefixToInfix(prefix);
+    
+    return 0;
+}

DS/C/Lab/Week6/PrefixToPostfix.c

@@ -0,0 +1,63 @@
+#include <stdio.h>
+#include <string.h>
+
+#define MAX_SIZE 100
+
+char stack[MAX_SIZE][MAX_SIZE];
+int top = -1;
+
+void push(const char* item) {
+    if (top >= MAX_SIZE - 1) {
+        printf("Stack Overflow\n");
+        return;
+    }
+    strcpy(stack[++top], item);
+}
+
+char* pop() {
+    if (top < 0) {
+        printf("Stack Underflow\n");
+        return NULL;
+    }
+    return stack[top--];
+}
+
+int isOperator(char c) {
+    return (c == '+' || c == '-' || c == '*' || c == '/');
+}
+
+int isAlphanumeric(char c) {
+    return ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z'));
+}
+
+void prefixToPostfix(char* prefix) {
+    int len = strlen(prefix);
+    char temp[MAX_SIZE];
+    
+    for (int i = len - 1; i >= 0; i--) {
+        if (isAlphanumeric(prefix[i])) {
+            temp[0] = prefix[i];
+            temp[1] = '\0';
+            push(temp);
+        } else if (isOperator(prefix[i])) {
+            char op1[MAX_SIZE], op2[MAX_SIZE], result[MAX_SIZE];
+            strcpy(op1, pop());
+            strcpy(op2, pop());
+            sprintf(result, "%s%s%c", op1, op2, prefix[i]);
+            push(result);
+        }
+    }
+    
+    printf("Postfix expression: %s\n", stack[top]);
+}
+
+int main() {
+    char prefix[MAX_SIZE];
+    printf("Enter prefix expression: ");
+    fgets(prefix, MAX_SIZE, stdin);
+    prefix[strcspn(prefix, "\n")] = 0;  // Remove newline if present
+    
+    prefixToPostfix(prefix);
+    
+    return 0;
+}