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Simple C Program That Checks For Duplicate Numbers

The program asks the user to enter numbers into the standard input. The numbers are checked for duplication first. If they are not duplicate, they are put into an array. 
    #define SIZE 5
   int isDupe(int numbers[SIZE],int num);

 	void main(void)
 	{
		 int numbers[SIZE];
		 int i =0, y;
		 int num;

		while(i<SIZE){
			printf("Enter a number:");
			scanf("%d", &num);
			printf("you entered %d\n", num);

			if(isDupe2(numbers, num)==1){
				numbers [i]= num;
				i++;
			}
		}

		for(y=0; y<SIZE; y++){
			printf("element %d value %d\n", y, numbers[y]);
		}
	 }

	int isDupe(int numbers[], 	int num){
		int i;
		for(i=0; i<SIZE; i++){
			if(numbers[i]== num){
				return 0;
			}
		}
		return 1;
	}

We can re-write the isDupe function using the pointers as follows: 

int isDupe2 (int *number,int num){
	int i;
	for(i=0; i <SIZE; i++){
		if(*number == num){
			return 0;
		}
		else
			number++;
	}
	return 1;
}