D:将字符串中的小写字母转换成大写字母

 1 #include <iostream>
 2 #include <string>
 3 using namespace std;
 4 int main()
 5 {
 6     string s;
 7     //cin>>s;//不能存入空格
 8     getline(cin,s);
 9     for (int i=0;i<s.length();++i)
10     {
11         if (s[i]>='a'&&s[i]<='z')
12         {
13             s[i] = s[i] - 32;
14         }
15     }
16     cout << s;
17     return 0;
18 }

 1 #include <iostream>
 2 #include <iomanip>
 3 #include <cstring>
 4 using namespace std;
 5 int main()
 6 {
 7     char str[100];
 8     int i, len;
 9     gets_s(str);
10     len = strlen(str);
11     for (i = 0; i < len; i++) {
12         if (str[i] >= 'a' && str[i] <= 'z') {
13             str[i] += 'A' - 'a';
14         }
15     }
16     cout << str;
17     return 0;
18 }