130 lines
3.0 KiB
C
130 lines
3.0 KiB
C
#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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#define STACK_SIZE 10
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struct stack {
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float values[STACK_SIZE];
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int size;
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};
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void init(struct stack *s) {
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s->size = 0;
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}
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void push_stack(struct stack *s, float value) {
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if (s->size < STACK_SIZE) {
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s->values[s->size] = value;
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s->size++;
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} else {
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printf("no input.\n");
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exit(1); // Exit the program on overflow
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}
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}
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float pop_stack(struct stack *s) {
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if (s->size > 0) {
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s->size--;
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return s->values[s->size];
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} else {
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printf("no input\n");
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exit(1); // Exit the program on underflow
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}
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}
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void print_stack(struct stack *s) {
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if (s->size > 0) {
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for (int i = 0; i < s->size; i++) {
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printf("%.2f ", s->values[i]);
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}
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printf("\n");
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}
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}
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int read(struct stack *s) {
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char temp[100];
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// Read a line of input
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if (fgets(temp, sizeof(temp), stdin) == NULL) {
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printf("no input\n");
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return 0; // Error reading input or end of input
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}
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// Check for empty input
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if (strcmp(temp, "\n") == 0) {
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return 1; // Continue to next iteration
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}
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// Check for termination input
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if (strcmp(temp, "end\n") == 0) {
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printf("no input\n"); // Print "no input" upon end
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return 0;
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}
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float value;
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char extra;
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int scan = sscanf(temp, "%f %c", &value, &extra);
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// If it's a properly formatted number
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if (scan == 1) {
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push_stack(s, value);
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print_stack(s);
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} else if (scan > 1) {
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// If extra characters were found, it's an invalid input like .23.4
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printf("bad input\n");
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exit(0);
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} else {
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switch (temp[0]) {
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case '+':
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case '-':
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case '*':
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case '/': {
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if (s->size < 2) {
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printf("no input\n");
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return 1; // Continue to next iteration
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}
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float b = pop_stack(s);
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float a = pop_stack(s);
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float result;
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switch (temp[0]) {
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case '+': result = a + b; break;
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case '-': result = a - b; break;
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case '*': result = a * b; break;
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case '/':
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if (b == 0) {
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printf("division by zero\n");
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exit(0);
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}
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result = a / b;
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break;
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}
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push_stack(s, result);
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print_stack(s);
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return 1; // Continue without printing "no input"
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}
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default:
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printf("bad input\n");
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exit(0); // Exit on invalid input
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}
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}
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return 1; // Continue the loop
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}
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int main() {
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struct stack my_stack;
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init(&my_stack);
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while (1) {
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if (read(&my_stack) == 0) {
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break;
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}
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}
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return 0;
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}
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