日志17
1.第一次只出现一次的字符
#include<bits/stdc++.h>
using namespace std;
int main() {
string s;
cin >> s;
vector<int> count(26, 0);
for (char c : s) {
count[c - 'a']++;
}
for (char c : s) {
if (count[c - 'a'] == 1) {
cout << c << endl;
return 0;
}
}
cout << -1 << endl;
return 0;
}
2.回文拼接
#include<bits/stdc++.h>
using namespace std;
int main() {
int n;
string s;
cin >> n;
for(int i = 1; i <= n; i++) {
cin >> s;
int len = s.length();
bool flag = 0;
for(int j = 2; j <= len - 2; j++) { //枚举第一段字符长度
string s1 = s.substr(0, j);
string s2 = s.substr(j, len - j + 1);
string t1 = s1;
string t2 = s2;
reverse(t1.begin(), t1.end());//翻转
reverse(t2.begin(), t2.end());//翻转
if (s1 == t1 && s2 == t2) {//如果都是回文串
flag = 1;//标记为回文拼接
break;
}
}
if(flag == 1) {
cout << "Yes" << endl;
} else {
cout << "No" << endl;
}
}
return 0;
}
