On using a string with the roman character 'I' its giving 8 instead of 1. similarly 24 instead of 3 for 'III'

Akshat kant 0
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The rest of the part which includes string like 'IV' are yet to be done, but right now the problem is for 'I' the program is returning 8 instead of 1;

#include <bits/stdc++.h> //header file
using namespace std;
  
int romantoint(char str[],int &n)
{
    int total=0;
    unordered_map <char,int> m;
    m['I'] = 1;
    m['II'] = 2;
    m['III'] = 3;
    m['IV'] = 4;
    m['V'] = 5;
    m['VI'] = 6;
    m['VII'] = 7;
    m['VIII'] = 8;
    m['IX'] = 9;
    m['X'] = 10;

    for(int i=0;i<n;i++)
    {
      total = total+m[str[i]];
    }

    return total;
    
}




int main()
{
  char str[] = "I";
  int n = strlen(str);
  cout<<romantoint(str,n);
}
c++11 c++17 c++
1 Answers
 unordered_map <char,int> m;

This line tells the compiler that you are going to be mapping a character to an integer. Whereas when you've initialized the map, you've instead mapped the string value of 'VIII' to 8. Since the key HAS to be a character, you're actually overwriting the m['I']= 1 map when you're mapping m['VIII']=8 . This is the reason you're getting 8 when you try to find the value mapped to m['I'] since the key is NOT supposed to be anything more than a single character.

P.S this looks like a function from which you want to return the corresponding integer value taking in it's roman numeral equivalent.
I would suggest using the same unordered_map <char,int> m;map, but instead of directly mapping VIII to 8, rather use the maps from V (=5) and I (=1) to figure out the value of VIII using program logic ;)

userlfzG0
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