here's my code,what's wrong with it,i get WA on test#8.
#include <iostream>
using namespace std;

int main(){

    char str[1000];
    int sum = 0;

    for(int i = 0; str[i] != '\0'; ++i){

        if(str[i] >= 'a' && str[i] <= 'z'){

            sum += (str[i] - 97) % 3 + 1;

        }else if(str[i] == ' ' || str[i] == '.'){

            ++sum;

        }else if(str[i] == '!'){

            sum += 3;

        }else if(str[i] == ','){

            sum += 2;

        }

    }
    cout << sum;
    return 0;

}

    char str[1002];