1.判断是否是大小写字母#include iostream using namespace std; int main() { char c; cin c; if (c A c Z) { cout BIG endl; } else if (c a c z) { cout SMALL endl; } else { cout NO endl; } return 0; }2.大小写转换#include iostream using namespace std; int main() { int n; cin n; char s[105]; cin s; for (int i 0; i n; i) { if (s[i] a s[i] z) { s[i] s[i] - 32; } } cout s endl; return 0; }3.打印小写字母表#include iostream using namespace std; int main() { char ch a; for (int i 0; i 13; i) { cout ch; ch; } cout endl; for (int i 0; i 13; i) { cout ch; ch; } cout endl; ch z; for (int i 0; i 13; i) { cout ch; ch--; } cout endl; ch m; for (int i 0; i 13; i) { cout ch; ch--; } cout endl; return 0; }4.元音字母#include iostream using namespace std; int main() { char c; cin c; if (c a || c e || c i || c o || c u) { cout Vowel endl; } else { cout Consonant endl; } return 0; }5.大写字母出现的个数#include iostream using namespace std; int main() { int n; cin n; char s[105]; cin s; int cnt 0; for (int i 0; i n; i) { if (s[i] A s[i] Z) { cnt; } } cout cnt endl; return 0; }