Why Does getline() Behave Unexpectedly in a Loop After Using `>>`?

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getline() and Console Input in C

In C , the getline() function is used to extract a line of text from a stream, typically the console. However, when used multiple times in a loop, it may behave unexpectedly.

Problem:
When attempting to collect user input using getline() for strings and >> for integers and doubles, the user is unable to enter the first string. Instead, the console cursor jumps to the next input prompt after the second getline() call.

Explanation:
The issue stems from the mixing of getline() and >> operators. >> skips leading whitespace and reads input until it reaches a non-whitespace character. However, it leaves a newline character (n) in the input stream.

When getline() is called after >>, it reads the newline character as the empty string, resulting in the undesired behavior.

Solution:

1. Use Operator >> Consistently: If all input can be processed using >>, stick to that method.
2. Use getline() Consistently: If the input involves strings or a mix of types, exclusively use getline() and parse the numbers from the retrieved strings. This can be done using a stringstream or a library like Boost.

string line;
getline(cin, line);
int value = stoi(line); // Parse the number from the string

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