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import java .util .*;
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+
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public class RomanToInteger {
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-
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- /*
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- This function convert Roman number into Integer
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- @param A is Roman number string
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- */
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- public static int romanToInt (String A ) {
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- Map <Character , Integer > map = new HashMap <>();
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- map .put ('I' , 1 );
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- map .put ('V' , 5 );
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- map .put ('X' , 10 );
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- map .put ('L' , 50 );
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- map .put ('C' , 100 );
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- map .put ('D' , 500 );
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- map .put ('M' , 1000 );
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-
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- char c = A .charAt (A .length ()-1 );
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- char prev = ' ' ;
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-
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- int sum =0 ;
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-
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- int newPrev = 0 , currentNum =0 ;
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- for (int i = A .length () -1 ;i >=0 ;i --)
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- {
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- c = A .charAt (i );
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-
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-
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- if (prev != ' ' ) {
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- //checking current Number greater then previous or not
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- newPrev = map .get (prev ) > newPrev ? map .get (prev ) : newPrev ;
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- }
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-
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-
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- currentNum = map .get (c );
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-
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- if (currentNum >= newPrev ) //if current number greater then prev max previous then add
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- {
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- sum += currentNum ;
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- }
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- else {
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-
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- sum -= currentNum ; // subtract upcoming number until upcoming number not greater then prev max
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- }
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-
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- prev = c ;
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- }
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-
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- return sum ;
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- }
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+ private static Map <Character , Integer > map = new HashMap <>() {{
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+ put ('I' , 1 );
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+ put ('V' , 5 );
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+ put ('X' , 10 );
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+ put ('L' , 50 );
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+ put ('C' , 100 );
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+ put ('D' , 500 );
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+ put ('M' , 1000 );
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+ }};
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+
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+ /**
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+ * This function convert Roman number into Integer
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+ *
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+ * @param A Roman number string
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+ * @return integer
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+ */
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+ public static int romanToInt (String A ) {
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+
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+ char prev = ' ' ;
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+
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+ int sum = 0 ;
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+
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+ int newPrev = 0 ;
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+ for (int i = A .length () - 1 ; i >= 0 ; i --) {
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+ char c = A .charAt (i );
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- public static void main (String [] args ) {
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-
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-
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- int sum = romanToInt ("MDCCCIV" ) ;
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- System .out .println (sum );
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- }
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+ if (prev != ' ' ) {
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+ // checking current Number greater then previous or not
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+ newPrev = map .get (prev ) > newPrev ? map .get (prev ) : newPrev ;
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+ }
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- }
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+ int currentNum = map .get (c );
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+
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+ // if current number greater then prev max previous then add
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+ if (currentNum >= newPrev ) {
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+ sum += currentNum ;
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+ } else {
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+ // subtract upcoming number until upcoming number not greater then prev max
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+ sum -= currentNum ;
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+ }
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+
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+ prev = c ;
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+ }
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+
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+ return sum ;
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+ }
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+
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+ public static void main (String [] args ) {
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+ int sum = romanToInt ("MDCCCIV" );
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+ System .out .println (sum );
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+ }
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+ }
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