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: Wrong Answer)

/* ex 5_4
   KitamoriFumiya */

#include <stdio.h>
#include <string.h>

int main(void){
	int length, number, max_number, part[11], i, j; // length,number,max_number,i,jをint型の変数, partをACGT文字列の長さを調べて格納するための配列として宣言
	char letter[11]; // 文字列は10文字以下なので要素数を11とする
	scanf("%s", letter);
	// 文字列の長さを求める
	length = strlen(letter);
	number = 0; // ACGT文字列の長さの初期値は0
	// ACGT文字列を調べる
	for(i = 0; i < length; i++){
		number = 0; // ACGT文字列の長さの初期値は0
		// i番目の文字からA,T,C,Gのいづれかが続けば、その文字列の長さを数え、part[i]に記録
		for(j = i; j < length; j++){
			if(letter[j] == 'A' || letter[j] == 'C' || letter[j] == 'G' || letter[j] == 'T'){
				number++;
			}else break;
		}
		part[i] = number;
	}
	// 最長のACGT文字列の長さを求める
	max_number = part[0];
	for(i = 1; i < 12; i++){
		if(max_number <= number){
			max_number = part[i];
		}
	}
	// 最長のACGT文字列の長さを出力
	printf("%d\n", max_number);
	
	return 0;
}