Why use symbol & when using scanf in C?

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The use of the ampersand "&" in the scanf function in C is essential because it provides the address of the variable where the input value will be stored. Unlike printf, which only requires the value of the variable and does not modify it, scanf needs a pointer to the variable to directly change its value. This distinction is crucial for understanding how data is handled in C, as scanf modifies the variable by writing to its memory address, while printf simply reads and displays the value without altering it. The "&" operator is not merely a convention; it serves a functional purpose in enabling scanf to work correctly.
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Why use symbol "&" when using scanf in C?

When using scanf like in scanf("%d",&x); why do we use '&' before x? can't we write directly ,x as in printf command? Is it just a convention? I think it should have a reason.. they won't just put an "&" just like that
 
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"&x" means to generate a pointer to "x". Scanf needs a pointer to x in order to store the value and change "x". Printf uses a copy of the value of "x" passed as a parameter (usually on the stack), since it isn't changing the value of "x".
 

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