Roman to Integer
Given a roman numeral, convert it to an integer. ie given string of "LVIII" return 58
class Solution {
public int romanToInt(String s) {
Map<Character, Integer> m = new HashMap<>();
m.put('I', 1);
m.put('V', 5);
m.put('X', 10);
m.put('L', 50);
m.put('C', 100);
m.put('D', 500);
m.put('M', 1000);
int ans = 0;
for (int i = 0; i < s.length(); i++) {
if (i < s.length() - 1 && m.get(s.charAt(i)) < m.get(s.charAt(i + 1))) {
ans -= m.get(s.charAt(i));
} else {
ans += m.get(s.charAt(i));
}
}
return ans;
}
}
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