C in 100 Seconds: Pointers — Two Ways to Access the Same Memory | Episode 17

A pointer holds a memory address — not a value, but the location of a value. Ampersand gets the address. Star follows the address back to the value. Change the value through the pointer and the original variable changes too. int star ptr declares a pointer. Ampersand x gives the address of x. Star ptr reads or writes the value at that address. x started at forty-two — we changed it to ninety-nine through the pointer. Same memory, two ways to access it. Student code: https://github.com/GoCelesteAI/c-in-100-seconds/tree/main/episode17 What You'll Learn: • int *ptr — declaring a pointer • &x — getting the memory address of a variable • *ptr — dereferencing, following the pointer to the value • Writing through a pointer changes the original variable • %p format specifier for printing addresses Next: Episode 18 — Pointer Arithmetic #c #programming #100seconds #learnc #pointers #dereference #ampersand #memory #address #tutorial Tags c pointers, pointer dereference c, ampersand address c, star pointer c, memory address c, int pointer, c tutorial 2026, c beginner, 100 seconds, learn c, coding tutorial