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The C programming language made simple

Implementing a queue in C

#include <stdio.h> #include <string.h> #include <stdlib.h> int queue[256]; int count = 0; void insertIntoQueue(int x) { if (count == 256) { fprintf(stderr, "No more space in the queue\n"); return; } queue[count] = x; count++; } int removeFromQueue() { if (count == 0) { fprintf(stderr, "No elements to extract from queue\n"); return -1; } int res = queue[0]; int i; for (i = 0; i < count - 1; i++) { queue[i] = queue[i + 1]; } count--; return res; } int main(int argc, char* argv[]) { insertIntoQueue(1); insertIntoQueue(2); insertIntoQueue(3); insertIntoQueue(5); int i; int localCount = count; for (i = 0; i < localCount; i++) { printf("%d ", removeFromQueue()); } return 0; }