九度oj 1530 最長不重復子串，oj1530
原題鏈接：http://ac.jobdu.com/problem.php?pid=1530
字符串簡單題，看似O(n^2)的復雜度10000的數據量會tle，其實最長不重復子串不超過26個嘛。。。
如下：
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1 #include<algorithm>
2 #include<iostream>
3 #include<cstdlib>
4 #include<cstring>
5 #include<cstdio>
6 using std::max;
7 const int Max_N = 10010;
8 int vis[26];
9 char buf[Max_N];
10 void solve(){
11 int i, j, ans = 0, n = strlen(buf);
12 for (i = 0; i < n - 1; i++){
13 int t = 1;
14 memset(vis, 0, sizeof(vis));
15 vis[buf[i] - 'a'] = 1;
16 for (j = i + 1; j < n; j++){
17 if (!vis[buf[j] - 'a']){
18 vis[buf[j] - 'a'] = 1;
19 t++;
20 } else {
21 break;
22 }
23 }
24 ans = max(ans, t);
25 }
26 printf("%d\n", ans);
27 }
28 int main(){
29 #ifdef LOCAL
30 freopen("in.txt", "r", stdin);
31 freopen("out.txt", "w+", stdout);
32 #endif
33 while (~scanf("%s", buf)) solve();
34 return 0;
35 }
View Code
