How to provide Sentinel value at the end of Structure Array

c, sentinel, structure

Solution

Your sentinel must be of type `int` (or some other field within `struct student`), such as:

s[10].roll_no = -1;

Your `while` loop will be as follows:

while(ptr->roll_no != -1)
{
    ...
    ptr++;
}

Problem

I've created a structure of 10 elements (11th for sentinel value) and a structure pointer, assigning address of first structure element to it. ``` struct student { int roll_no; }; struct student s[11]; struct student *ptr = &s[0]; s[10] = NULL; // Sentinel value while (*ptr != NULL ) // Sentinel Controlled Loop { printf ("%d - ", ptr -> roll_no); ptr++; } ``` How do I provide a sentinel value in the end of a structure array ? EDIT : values in structure are changing dynamically i.e. i've created space for 10 structures but it might happen their will be only 5 elements present their at a moment. and sentinel value at 6th position. when user enters a new structure element, sentinel value shifts forward etc so i can not use a (int i < 10) condition to simply print all the values.

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