pvjc24/a1/program.c

#include <stdio.h>
#include <stdlib.h>

#define SIZE 1000

typedef struct{
    char* p_na_line;
    struct link* p_na_next_struct;
}link;

int main()
{
    link* pointer_to_start_of_chain = malloc(sizeof(link));
    memset(pointer_to_start_of_chain,0,sizeof(link));
    int read_lines = reading_strings_and_storing_them_in_memory(pointer_to_start_of_chain);
    if(read_lines==0){
        return 0;
    }
    int result=0;
    link* next_link = pointer_to_start_of_chain;
    while(next_link != NULL){
        result=analizing_string(next_link->p_na_line);
        if(result==0){
            printf("ZLE\n");
        }else if(result==1){
            printf("OK\n");
        }else{
            printf("CHYBA\n");
        }
        free(next_link->p_na_line);
        link* ptr=next_link;
        next_link=next_link->p_na_next_struct;
        free(ptr);
    }
    return 0;
}

int reading_strings_and_storing_them_in_memory(link* pointer_to_start_of_chain){
    link* next_link = pointer_to_start_of_chain;
    char buffer[SIZE];
    link* ancestor=NULL;
    int counter=0;
    while(1){
        if(fgets(buffer, SIZE, stdin)==NULL||buffer[0]=='\n'){
            free(next_link);
            if(ancestor!=NULL){
                ancestor->p_na_next_struct=NULL;
            }
            break;
        }

        int size=strlen(buffer)+1;

        next_link->p_na_line=malloc(size);
        next_link->p_na_next_struct=malloc(sizeof(link));

        memcpy(next_link->p_na_line, buffer,size);
        ancestor=next_link;
        next_link=next_link->p_na_next_struct;
        counter++;
    }
    return counter;
}
int analizing_string(char* pointer){
    char first_number[SIZE];
    char second_number[SIZE];
    char result_nubmer[SIZE];

    memset(first_number, 0, SIZE);
    memset(second_number, 0, SIZE);
    memset(result_nubmer, 0, SIZE);

    float number1, number2, result3;
    char operant;

    int i = 0;
    int counter=0;
    while(pointer[i]!='\0'){
        if(pointer[i]=='+'||pointer[i]=='/'||pointer[i]=='*'||pointer[i]=='-'){
            operant=pointer[i];
            counter++;
            if(counter>1){
                return -1;
            }
        }
        i++;
    }

    i = 0;
    // Look for the start of the first number.
    i = skip_spaces(i, pointer);

    // Copy first number to its destination.
    i = copy_number(first_number, pointer, i);

    // Look for the start of the operation;
    i = skip_spaces(i, pointer);
    // Processing operation.
    operant = pointer[i];
    i++;
    if (operant != '+' && operant != '-' && operant != '*' && operant != '/') {
        return -1;
    }

    // Look for the start of the second number;
    i = skip_spaces(i, pointer);

    // Copy second number to its destination.
    i = copy_number(second_number, pointer, i);

    // Look for the start of the "=";
    i = skip_spaces(i, pointer);
    // Processing "="
    if (pointer[i] != '=') {
        return -1;
    }
    i++;

    // Look for the start of the result number;
    i = skip_spaces(i, pointer);

    // Copy result number to its destination.
    i = copy_number(result_nubmer, pointer, i);

    // Look for the start of the "\n";
    i = skip_spaces(i, pointer);
    if ('\n' != pointer[i]) {
        return -1;
    }

    number1=atof(first_number);
    number2=atof(second_number);
    result3=atof(result_nubmer);

    if(operant=='+' &&result3==number1+number2){
        return 1;
    }
    if(operant=='-'&&(result3==number1-number2)){
        return 1;
    }
    if(operant=='*'&&(result3==number1*number2)){
        return 1;
    }
    if(operant=='/'&&(result3==number1/number2)){
        return 1;
    }
    return 0;
}

int skip_spaces(int i, char *pointer) {
    while(pointer[i]==' '){
        i++;
    }

    return i;
}

int copy_number(char number[], char *pointer, int i) {
    int destination_i = 0;
    while(pointer[i]!='\0'){
        if (!isdigit(pointer[i])&&pointer[i]!='.'&&pointer[i]!=',') {
            break;
        }
        number[destination_i] = pointer[i];
        destination_i++;
        i++;
    }

    return i;
}

/*int is_number_question_mark(char *pointer){
    for(int i=0; pointer[i]!='\0'; i++){
       if (!isdigit(pointer[i])&&pointer[i]!='.'&&pointer[i]!=',') {
            return 0;
        }
    }
    return 1;
}*/