📘 Day 18 – Teacher's Day Challenge | Bit++

🗓️ Date: August 11, 2025
🧩 Platform: Codeforces
🔢 Problems Solved Today: 1
🎯 Focus Topic: Strings, Conditional Statements

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🔗 Table of Contents

• Problem 1 – Bit++

• Daily Summary

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🧩 Problem 1 – Bit++

📚 Difficulty: Easy-Medium
🧠 Concepts: Strings, Increment/Decrement Operations

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📄 Problem Statement (Summary):
You are given n statements from the Bit++ programming language.
Each statement contains exactly one variable x and one operation:

• ++ increases x by 1

• -- decreases x by 1

Initially, x = 0.
Execute all statements in the given order and output the final value of x.

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🔢 Input Format:

• First line: integer n (1 ≤ n ≤ 150) – number of statements.

• Next n lines: each contains one statement (++X, X++, --X, or X--).

🧾 Output Format:
A single integer – the final value of x.

🔍 Example 1:
Input:

1
++X

Output:

1

🔍 Example 2:
Input:

2
X++
--X

Output:

0

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💡 Approach:

• Start with x = 0.

• For each statement:

  • If "++" is found in the string, increment x.

  • Otherwise, decrement x.

• Output the final value of x.

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🧪 Code (C++):

#include <iostream>
using namespace std;

int main() {
    int n, X = 0;
    string s;
    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> s;
        if (s.find("++") != string::npos)
            X++;
        else
            X--;
    }
    cout << X;
    return 0;
}

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📸 Submission Screenshot:

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✅ Key Takeaways:

• Detecting substrings with find() is a quick way to handle such pattern-based decisions.

• Order of characters in the statement doesn’t matter for the result.

• Initializing variables correctly at the start avoids logical errors.

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📈 Daily Summary

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🏷️ Tags:
#codeforces #strings #cpp #beginner #dsa #43DaysChallenge