Update cv3/program.c

cv3/program.c

@@ -1,116 +1,81 @@
 #include <stdio.h>
 #include <stdlib.h>
-#include <string.h>
-#include <assert.h>
-#include <ctype.h>
 
 #define STACK_SIZE 10
 
+double stack[STACK_SIZE];
+int top = 0;
 
-struct stack {
-    float values[STACK_SIZE];
-    int size;
-};
-
-
-void init_stack(struct stack* s) {
-    memset(s, 0, sizeof(struct stack));
-}
-
-
-void push_stack(struct stack* s, float value) {
-    assert(s->size < STACK_SIZE); 
-    s->values[s->size] = value;
-    s->size += 1;
-}
-
-
-float pop_stack(struct stack* s) {
-    assert(s->size > 0); 
-    s->size -= 1;
-    return s->values[s->size];
-}
-
-
-void print_stack(struct stack* s) {
-    for (int i = 0; i < s->size; i++) {
-        printf("%.2f ", s->values[i]);
+void print_stack() {
+    for (int i = 0; i < top; i++) {
+        printf("%.2f ", stack[i]);
     }
     printf("\n");
 }
 
-
-int is_number(const char* str) {
-    char* endptr;
-    strtof(str, &endptr);
-    return endptr != str && *endptr == '\0'; 
+int push(double value) {
+    if (top >= STACK_SIZE) {
+        printf("full stack\n");
+        return 0;
+    }
+    stack[top++] = value;
+    print_stack();
+    return 1;
 }
 
-
-int main() {
-    struct stack mystack;
-    init_stack(&mystack);
-
-    char input[20]; 
-
-    while (1) {
-        printf("Enter a number or an operation (+, -, *, /): ");
-        if (!fgets(input, sizeof(input), stdin)) {
-            break; 
+int pop(double *value) {
+    if (top <= 0) {
+        printf("not enough operands\n");
+        return 0;
+    }
+    *value = stack[--top];
+    return 1;
 }
 
+int apply_operation(char op) {
+    double a, b;
 
-        input[strcspn(input, "\n")] = 0;
-
-        if (is_number(input)) {
-            
-            float value = strtof(input, NULL);
-            push_stack(&mystack, value);
-            print_stack(&mystack);
-        } else {
-            
-            if (mystack.size < 2) {
-                printf("Error: Not enough values on the stack to perform operation.\n");
-                break; 
+    if (!pop(&b) || !pop(&a)) {
+        return 0;
     }
-            float b = pop_stack(&mystack);
-            float a = pop_stack(&mystack);
-            float result = 0; 
 
-            switch (input[0]) {
-                case '+':
-                    result = a + b;
-                    break;
-                case '-':
-                    result = a - b;
-                    break;
-                case '*':
-                    result = a * b;
-                    break;
+    double result;
+    switch (op) {
+        case '+': result = a + b; break;
+        case '-': result = a - b; break;
+        case '*': result = a * b; break;
         case '/':
             if (b == 0) {
-                        printf("Error: Division by zero.\n");
-                        
-                        push_stack(&mystack, a);
-                        push_stack(&mystack, b);
-                        print_stack(&mystack);
-                        continue; 
+                printf("division by zero\n");
+                return 0;
             }
             result = a / b;
             break;
         default:
-                    printf("Error: Unknown operation '%s'.\n", input);
-                    
-                    push_stack(&mystack, a);
-                    push_stack(&mystack, b);
-                    print_stack(&mystack);
-                    continue; 
-            }
-
-            push_stack(&mystack, result);
-            print_stack(&mystack);
-        }
-    }
-
+            printf("bad input\n");
+            return 0;
+    }
+
+    return push(result);
+}
+
+int main() {
+    char input[100];
+
+    while (scanf("%s", input) == 1) {
+        char *end;
+        double value = strtod(input, &end);
+
+        if (*end == '\0') {
+            if (!push(value)) return 0;
+        } else if (input[1] == '\0' && strchr("+-*/", input[0])) {
+            if (!apply_operation(input[0])) return 0;
+        } else {
+            printf("bad input\n");
+            return 0;
+        }
+    }
+
+    printf("no input\n");
     return 0;
 }