usaa21/cv3/program.c
2021-10-22 00:45:57 +02:00

144 lines
4.2 KiB
C

#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <stdlib.h>
#define STACK_SIZE 10
struct stack{
float values[STACK_SIZE];
int size;
};
void print_stack(struct stack* stack);
void push_stack(struct stack* stack, float value);
float pop_stack(struct stack* stack);
int main(){
char char_value[STACK_SIZE];
memset(&char_value,0,STACK_SIZE);
float float_value;
char* ptr;
struct stack myStack;
memset(&myStack,0,sizeof(struct stack));
while(1){
if(myStack.size == 9){
//print_stack(&myStack);
puts("full stack");
break;
}
ptr = fgets(char_value, STACK_SIZE-1, stdin);
if(ptr != NULL){
if(char_value[0] == '\n'){
puts("no input");
break;
}
/*if(char_value[0] == '0'){
push_stack(&myStack,0);
print_stack(&myStack);
printf("\n");
continue;
}*/
if(char_value[0] == '+'){
if(myStack.size > 1){
float a = pop_stack(&myStack);
float b = pop_stack(&myStack);
float c = a+b;
push_stack(&myStack, c);
print_stack(&myStack);
printf("\n");
}else{puts("not enough operands"); break;}
}else if(char_value[0] == '-'){
if(myStack.size > 1){
float a = pop_stack(&myStack);
float b = pop_stack(&myStack);
float c = b-a;
push_stack(&myStack, c);
print_stack(&myStack);
printf("\n");
}else{puts("not enough operands"); break;}
}else if(char_value[0] == '*'){
if(myStack.size > 1){
float a = pop_stack(&myStack);
float b = pop_stack(&myStack);
float c = a*b;
push_stack(&myStack, c);
print_stack(&myStack);
printf("\n");
}else{puts("not enough operands"); break;}
} else if(char_value[0] == '/'){
if(myStack.size > 1){
float a = pop_stack(&myStack);
if(a == 0){
printf("division by zero\n");
break;
}else{
float b = pop_stack(&myStack);
float c = b/a;
push_stack(&myStack, c);
print_stack(&myStack);
printf("\n");
}
}else{puts("not enough operands"); break;}
} else if(isdigit(char_value[0]) != 0 ){
float_value = strtof(char_value, NULL);
//printf("float value: %f\n",float_value);
/*if(float_value == 0){
puts("bad input");
break;*/
//} else {
push_stack(&myStack,float_value);
print_stack(&myStack);
printf("\n");
continue;
} else {
puts("bad input");
break;
}
} else {
//push_stack(&myStack, float_value);
//print_stack(&myStack);
//printf("\n");
puts("no input");
break;
}
}
return 0;
}
void print_stack(struct stack* stack){
for(int i = 0; i < stack->size; i++){
printf("%.2f ",stack->values[i]);
}
}
void push_stack(struct stack* stack, float value){
//assert(stack->size < STACK_SIZE);
stack->values[stack->size] = value;
stack->size += 1;
}
float pop_stack(struct stack* stack){
//assert(stack->size > 0);
float value = stack->values[stack->size-1];
stack->size -= 1;
return value;
}