Question

I have an array which contains some strings. For each character of a string an integer value is assigned. For example a=2,b=5,c=6 ,o=1,k=3 etc

The final value in the a string is the sum of the character’s value. So that for an example string “BOOK” the string will be stored as “BOOK (7)”. Similarly every string will have a final integer value. I would like to sort these array with these final integer values stored in the string which is present in each array index. The array contains more than 200,000 words. So the sorting process should be pretty fast. Is there any method for it?

Answer 1

A brutal quick example could be, if your strings structure is always the same, like “Book (7)” you can operate on the string by finding the number between the “()” and then you can use a dictionary to store temporally the objects:

    NSMutableArray *arr=[NSMutableArray arrayWithObjects:@"Book (99)",@"Pencil (66)",@"Trash (04)", nil];
    NSLog(@"%@",arr);

    NSMutableDictionary *dict=[NSMutableDictionary dictionary];
    //Find the numbers and store each element in the dictionary 
    for (int i =0;i<arr.count;i++) {
        NSString *s=[arr objectAtIndex:i];
        int start=[s rangeOfString:@"("].location;
        NSString *sub1=[s substringFromIndex:start];
        NSString *temp1=[sub1 stringByReplacingOccurrencesOfString:@"(" withString:@""];
        NSString *newIndex=[temp1 stringByReplacingOccurrencesOfString:@")" withString:@""];
        //NSLog(@"%d",[newIndex intValue]);
        [dict setValue:s forKey:newIndex];
    }
    //Sorting the keys and create the new array
    NSArray *sortedValues = [[dict allKeys] sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];
    NSMutableArray *newArray=[[NSMutableArray alloc]init];
    for(NSString *valor in sortedValues){
               [newArray addObject:[dict valueForKey:valor]];
        }
    NSLog(@"%@",newArray);

This prints:

(
“Book (99)”,
“Pencil (66)”,
“Trash (04)”
)

(
“Trash (04)”,
“Pencil (66)”,
“Book (99)”
)