字符串奇数位和偶数位的位数之和

def calculate_sum(string):
    odd_sum = 0
    even_sum = 0
    for i in range(len(string)):
        if i % 2 == 0:  # 奇数位
            odd_sum += int(string[i])
        else:  # 偶数位
            even_sum += int(string[i])
    return odd_sum + even_sum

string = "abcdefg"
result = calculate_sum(string)
print("字符串奇数位和偶数位的位数之和为:", result)