I need help with my Roman number code (C language)

Asked

Viewed 112 times

0

Well, I created this code as a draft form for the project I have in which it turns certain words into decimal values, but I did it with Roman numerals pq is easier that way for now, but there’s a problem, every time I do XL that should give the value of 40, is calculated as 60, and when I do LX that should give 60 gives -40, likely to be a logic problem, but I’m not able to find where I’m missing in this code, I thank you already.

PS: The rest works good, IV gives 4 right and IX gives 9 also normal, for example.

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

int cot2dec(char s[100]){
    
    int i, c = 0, valor;
    char s2[100];
    
    for(i=0; i<strlen(s); i++){
        
        if(s[i] > s[i+1]){
            
            switch(s[i]){
                case 'I':
                    valor=1;
                    break;
                case 'V':
                    valor=5;
                    break;
                case 'X':
                    valor=10;
                    break;
                case 'L':
                    valor=50;
                    break;
                default:
                    printf("insira um valor valido.");
                    break;
            }
            c+=valor;
        } else if(s[i] < s[i+1]){
            switch(s[i]){
                case 'I':
                    valor=1;
                    break;
                case 'V':
                    valor=5;
                    break;
                case 'X':
                    valor=10;
                    break;
                case 'L':
                    valor=50;
                    break;
                default:
                    printf("insira um valor valido.");
                    break;
            }
            c-=valor;
            
            } else if(s[i] == s[i+1]){
            
                switch(s[i]){
                    case 'I':
                        valor=1;
                        break;
                    case 'V':
                        valor=5;
                        break;
                    case 'X':
                        valor=10;
                        break;
                    case 'L':
                        valor=50;
                        break;
                    default:
                        printf("insira um valor valido.");
                        break;
                }
                c+=valor;
        }
    }
    
    return c;
}


int main() {
    char cad[100];

    int cotinter;
    
    printf("Insira um algarismo romano: ");
    scanf("%s", &cad);
    cotinter = cot2dec(cad);
    printf("O valor decimal de %s e %d", cad, cotinter);
    
    
    return 0;
}
c logic

  • I think it’s complex, I answered some questions about: https://answall.com/search?q=user%3A101+romano But I don’t know if any will do. It seems to me that logic is disregarding the correct positions that I Roman changes, but I have not analyzed profitably.

  • yes, but the problem seems to me to be in the combination of X and L, since the other combinations work normally.

1 answer

0

The code problem is on these lines:

  if(s[i] > s[i+1])
  if(s[i] < s[i+1])

You are comparing char, and this comparison is made by the value of the ASCII table. For example, X is worth 10 in Roman numerals, while L Vale 50, however when comparing the two X is greater than L, because in the table ASCII X = 88, L = 76. And you want X to be smaller.

int convertValor(char s[100]){
int valS[100];
int i, j, c = 0, valor;

for(j=0; j<strlen(s); j++){
    if(s[j] == 'I'){
          valS[j] = 1;
    }else if(s[j] == 'V'){
        valS[j] = 5;
    }
    else if(s[j] == 'X'){
        valS[j] = 10;
    }
    else if(s[j] == 'L'){
        valS[j] = 50;
    }

}
valS[strlen(s)] = 0;

for(i=0; i<strlen(s); i++){
    if(valS[i] > valS[i+1]){
        printf("Valor MAIOR %d\n",valS[i]);

        switch(valS[i]){

            case 1:
                valor=1;
                break;
            case 5:
                valor=5;
                break;
            case 10:
                valor=10;
                break;
            case 50:
                valor=50;
                break;
            default:
                printf("insira um valor valido.");
                break;
        }
        c+=valor;
    } else if(valS[i] < valS[i+1]){
        printf("Valor MENOR %d\n",valS[i]);
        switch(valS[i]){
            case 1:
                valor=1;
                break;
            case 5:
                valor=5;
                break;
            case 10:
                valor=10;
                break;
            case 50:
                valor=50;
                break;
            default:
                printf("insira um valor valido.");
                break;
        }
        c -=valor;

        } else if(valS[i] == valS[i+1]){

            switch(valS[i]){
                case 1:
                    valor=1;
                    break;
                case 5:
                    valor=5;
                    break;
                case 10:
                    valor=10;
                    break;
                case 50:
                    valor=50;
                    break;
                default:
                    printf("insira um valor valido.");
                    break;
            }
            c+=valor;
    }
}

return c;

}

https://web.fe.up.pt/~ee96100/project/Table%20ascii.htm

Browser other questions tagged c logic

You are not signed in. Login or sign up in order to post.