CodeForces

水题

#include <iostream>#include <cstdio>#include <cstdlib>#include <cstring>#include <string>#include <cmath>#include <set>#include <map>#include <stack>#include <queue>#include <ctype.h>#include <vector>#include <algorithm>#include <sstream>#define PI acos(-1.0)#define in freopen("in.txt", "r", stdin)#define out freopen("out.txt", "w", stdout)using namespace std;typedef long long ll;const int maxn = 200 + 7, INF = 0x3f3f3f3f, mod = 1e9 + 7;int n;char s[maxn];set<char> st;int main() {    scanf("%d", &n);    scanf("%s", s);    s[n] = 'D';    int max_ = 0;    for(int i = 0; i <= n; ++i) {        if(s[i] >= 'a' && s[i] <= 'z') {            st.insert(s[i]);        }        else {            max_ = max(max_, (int)st.size());            st.clear();        }    }    printf("%d\n", max_);    return 0;}