B002.c

#include <stdio.h>
#include <string.h>

// 定数
enum {
    N = 26,
};

int main()
{
    int resistances[N];
    char alphabets[N];
    long long answer;

    int n;
    int i;
    char alphabet;
    int resistance;
    int len;
    double tmp;

    scanf("%d\n", &n);
    for (i = 0; i < n; i++) {
        scanf("%c %d\n", &alphabet, &resistance);
        resistances[alphabet - 'A'] = resistance;
    }

    answer = 0;

    while (scanf("%s", alphabets) != EOF) {
        len = strlen(alphabets);
        if (len == 1) {
            answer += resistances[alphabets[0] - 'A'];
        } else {
            tmp = 0.0;
            for (i = 0; i < len; i++) {
                tmp += (double)1.0 / (double)resistances[alphabets[i] - 'A'];
            }
            answer += (long long)( (double)1.0 / tmp );
        }
    }

    printf("%lld\n", answer);

    return 0;
}