cses

commit b4c9537fd8f13fcfc990f03b3731950fb6ae3759
parent 3d1f61c860eed7b034d5673197cdc04b5555f8e5
Author: Jack Sangdahl <jack@pngu.org>
Date:   Wed, 18 Dec 2024 10:56:03 -0700

1069. repetitions

Diffstat:
M
introductory_problems/readme.md
 | 
7
+++++++
A
introductory_problems/repetitions.cpp
 | 
16
++++++++++++++++

2 files changed, 23 insertions(+), 0 deletions(-)
diff --git a/introductory_problems/readme.md b/introductory_problems/readme.md
@@ -13,3 +13,10 @@ You are given all numbers between `1, 2, ..., n` except one. Your task is to fin
 **Input**: The first input line contains an integer `n`. The second input line contains `n - 1` numbers. Each number is distinct and between 1 and `n` (inclusive). (Example: 5`\n`2 3 1 5)
 
 **Output**: Print the missing number. (Example: 4)
+
+### Repetitions
+You are given a DNA sequence: a string consisting of A, C, G, and T. Your task is to find the longest repetition in the sequence. This is a maximum-length substring containing only one type of character.
+
+**Input**: The only input line contains a string of `n` characters. (Example: ATTCGGGA)
+
+**Output**: Print one integer: the length of the longest repetition. (Example: 3)
diff --git a/introductory_problems/repetitions.cpp b/introductory_problems/repetitions.cpp
@@ -0,0 +1,16 @@
+// 1069. Repetitions
+#include <bits/stdc++.h>
+using namespace std;
+
+const int max_size = 1e6 + 5;
+
+int main() {
+  char str[max_size];
+  scanf(" %s", str);
+  int num = strlen(str), curr = 1, cnt = 1;
+  for (int i = 1; i < num; i++) {
+    curr = str[i] == str[i - 1] ? curr + 1 : 1;
+    cnt = max(cnt, curr);
+  }
+  printf("%d\n", cnt);
+}