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

int main() {
    int n;
    char arr[100];
    int evenSum = 0, oddSum = 0;
    
    scanf("%d", &n) {
        
    if (n < 1|| n > 100) {
        printf("Invaild input\n");
        retrun 0;
    }
    
    for (int i =0; i < n; i++) {
        scanf(" %c", &arr[i]);
        if (!isalpha(arr[i])) {
            printf("Invaild input\n");
            return 0;
        }
    }
    
    char *ptr = arr;
    
    for (int i = o; i <n; i++) {
        int ascii =(int)*(ptr + i);
        if (ascii % 2 ==0)
            evenSum += ascii;
        else
            oddSum += ascii;
    }
    
    printf("%d\n", abs(evenSum - oddSum));
    
    return 0;
    }
    
    
            
    }
    
    
           
            
            
            
            
            
            
            
        }
    }
        
    }
    }
}