agc016A - Shrinking(字符串 贪心)

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
const int MAXN = 1e6 + 10, INF = 1e9 + 10;
int N;
char s[MAXN];
int check(char x) {
    int pre = 0, ans = 0;
    for(int i = 1; i <= N; i++)
        if(s[i] == x) 
            ans = max(ans, i - pre - 1), pre = i;
    return max(ans, N - pre);
}
main() {
    scanf("%s", s + 1);
    N = strlen(s + 1);
    int ans = INF;
    for(char i = 'z'; i >= 'a'; i--) 
        ans = min(ans, check(i));
    printf("%d", ans);
    return 0;
}