5 a?bb? 3 aaa
aabba QwQ
AC代码:
#include <cstdio>
#include <cstring>
#include <algorithm>
#define LL long long
using namespace std;
char str[1005];
int len;
int flag;
int judge() {
for(int i = 0; i <= len / 2; i++) {
if(str[i] != str[len - i - 1]) return 1;
}
return 0;
}
void dfs(int x) {
if(flag == 0) return;
if(x == len) {
if(judge()) {
printf("%s\n", str);
flag = 0;
}
return;
}
if(str[x] <= 'z' && str[x] >= 'a') {
dfs(x + 1);
return;
}
if(str[x] == '?') {
for(int i = 'a'; i <= 'z'; i++) {
str[x] = (char)i;
dfs(x + 1);
str[x] = '?';
}
}
}
int main() {
int n;
while(scanf("%d", &n) != EOF) {
scanf("%s", str);
len = strlen(str);
flag = 1;
dfs(0);
if(flag) {
printf("QwQ\n");
}
}
return 0;
}
HDU - 5202 - Rikka with string (DFS)
原文地址:http://blog.csdn.net/u014355480/article/details/45000903