C语言（关于字符串的编程题） C语言

题目如下：
You’ve gathered some e-mail addresses from a variety of sources, and you want to send out a mass mailing to all of the addresses. However, you don’t want to send out duplicate messages. You need to write a program that reads all e-mail addresses and discards any that already have been input.
Input
The first line is a positive integer for the number of e-mail addresses which is smaller than 50. Then each of the e-mail addresses is input in one line.
Output
Output the new mailing list in lexicographic order. Each e-mail address in one line.
Note: ignore letter case when comparing two e-mail addresses, but the output is case sensitive.
Sample Input
10
toocle01@netsun.com
chuangling@chuangling.net
zjykrc@163.com
hahdjx@163.com
5663@sohu.com
toocle01@netsun.com
chenql_008@163.com
tsmoql@alibaba.com.cn
LYC@hzlasiji.com
zjykrc@163.com
Sample Output
5663@sohu.com
chenql_008@163.com
chuangling@chuangling.net
hahdjx@163.com
LYC@hzlasiji.com
toocle01@netsun.com
tsmoql@alibaba.com.cn
zjykrc@163.com
【C语言（关于字符串的编程题）】题目的意思是输入一堆电子邮箱的地址，让我们设计一个程序，能够剔除重复的邮箱地址并将邮箱地址按照字母表顺序排列。在比较字符串的时候，字母的大小写可以忽略，但是在输出的时候，字母的大小写要纳入考虑的范围。即根据ASCII。

# include # include char* strlwr(char copy[100]) { for (int i = 0; i < strlen(copy); i++) { if (copy[i] <= 'Z' && copy[i] >= 'A') copy[i] += 32; } return copy; } int main(void) { int T; scanf("%d", &T); char address[50][100]; int i = 0, len = 0; while (i < T) { i++; scanf("%s", address[len]); for (int j = 0; j < len; j++) { if (strcmp(address[len], address[j]) == 0) { len--; break; } } len++; } for (int j = 0; j < len-1; j++) for (int k = 0; k < len-1-j; k++) { char copy2[100], copy3[100]; snprintf(copy2, sizeof(copy2), "%s", address[k]); snprintf(copy3, sizeof(copy3), "%s", address[k+1]); if (strcmp(strlwr(copy2), strlwr(copy3)) > 0) { char copy[100]; snprintf(copy, sizeof(copy), "%s", address[k]); snprintf(address[k], sizeof(address[k]), "%s", address[k+1]); snprintf(address[k+1], sizeof(address[k+1]), "%s", copy); } } for (int j = 0; j < len; j++) { printf("%s\n", address[j]); } return 0; }

以上内容皆为本人观点，欢迎大家提出批评和指导，我们一起探讨！