UVA1610 PartyGame 聚会游戏（细节题）

#include<bits/stdc++.h>
using namespace std;

vector<string> vec;

int main()
{
// freopen("in.txt","r",stdin);
int n;
char s[142];
while(scanf("%d",&n),n){
vec.resize(n);
for(int i = 0; i < n; i++){
scanf("%s",s);
vec[i] = s;
}
sort(vec.begin(),vec.end());
int mid = n>>1;
string &a = vec[mid-1] ,&b = vec[mid];
int i;
int len1 = a.size()-1, len2 = b.size()-1;
if(len1 < len2){
for(i = 0; i < len1; i++){
if(b[i] != a[i]) { s[i] = a[i]+1; s[i+1] = '\0'; break; }
s[i] = a[i];
}
if(i == len1) {
s[i] = a[i]; s[i+1] = '\0';
}
}else if(len1>len2){
for(i = 0; i < len2; i++){
if(b[i] != a[i]) { s[i] = a[i]+1; s[i+1] = '\0'; break; }
s[i] = a[i];
}
if(i == len2) {
if(b[i] != a[i]+1) { s[i] = a[i]+1; s[i+1] = '\0'; }
else {
s[i] = a[i];
for(i++; i < len1; i++){
if(a[i] != 'Z'){
s[i] = a[i] + 1; s[i+1] = '\0'; break;
}
s[i] = a[i];
}
if(i == len1) { s[i] = a[i]; s[i+1] = '\0'; }
}
}
}else {
for(i = 0; i < len2; i++) {
if(b[i] != a[i]) { s[i] = a[i]+1; s[i+1] = '\0'; break; }
s[i] = a[i];
}
if(i == len2) { s[i] = a[i]; s[i+1] = '\0';  }
}
printf("%s\n",s);
}
return 0;
}