Problem:
Score : 200 points

Problem Statement

You are given a string S consisting of uppercase English letters. Find the length of the longest ACGT string that is a substring (see Notes) of S.

Here, a ACGT string is a string that contains no characters other than A, C, G and T.

Notes

A substring of a string T is a string obtained by removing zero or more characters from the beginning and the end of T.

For example, the substrings of ATCODER include TCO, AT, CODER, ATCODER and (the empty string), but not AC.

Constraints

S is a string of length between 1 and 10 (inclusive).

Each character in S is an uppercase English letter.

Input

Input is given from Standard Input in the following format:

S

Output

Print the length of the longest ACGT string that is a substring of S.

Sample Input 1

ATCODER

Sample Output 1

3

Among the ACGT strings that are substrings of ATCODER, the longest one is ATC.

Sample Input 2

HATAGAYA

Sample Output 2

5

Among the ACGT strings that are substrings of HATAGAYA, the longest one is ATAGA.

Sample Input 3

SHINJUKU

Sample Output 3

0

Among the ACGT strings that are substrings of SHINJUKU, the longest one is (the empty string).

Solution in C (GCC 9.2.1) (judge verdict: Accepted)

/* ex 5_4
   Rikuta */

#include <stdio.h>
//strlenを使うためのヘッダファイルのインクルード
#include <string.h>

int main(void)
{ 
    //最高文字列数は10なのでヌル文字も含め11
    char sequence[11];
    //最大の長さと何文字連続しているかが入る配列の初期化
    int i,max = 0,array[10]={0};
    //入力
    scanf("%s", sequence);
    for ( i = 0; i < strlen(sequence); i++)
    {   
        //読み取った文字が，A,C,G,Tで，
        if (sequence[i]=='A'||sequence[i]=='C'||sequence[i]=='G'||sequence[i]=='T')
        {   
            if (i==0)
            {   
                //最初の文字の時は連続1文字目
                array[i] = 1;
            }
            else
            {   
                //最初の文字でない時は，前の連続数に1を足したものが
                //その連続数．
                array[i] = array[i - 1] + 1;
            }
            if (array[i] >= max)
            {   
                //その連続数が最高記録ならば最高記録を更新
                max = array[i];
            }
        }
    }
    //最高連続記録の出力
    printf("%d\n", max);
    return 0;
}