Thread: if problem

Problem is when i press B as the center element the line at the end "if(centerelement=="B") should run what inside.

I put this inside the if statement:

Code:

VEC = 3;
printf("%d",VEC);

I put the printf so i can verify that the value of VEC is now 3.

Here is the source code:

Code:

#include <stdio.h>
#include <stdlib.h>

int main()
{
	char charselect[1];
	int select;

	char tempelement[3];

	char centerelement[3];
	char pelement1[3]; //periferal element 1
	char pelement2[3]; //periferal element 2
	char pelement3[3]; //periferal element 3
	char pelement4[3]; //periferal element 4

	int totalVE; //total valance electrons

	int VEC; //# of valance electrons in center
	int VE1;
	int VE2;
	int VE3;
	int VE4;
	
/*	H = 1;
	B = 3;
	C = 4;
	N = 5;
	P = 5;
	O = 6;
	S = 6;
	Se = 6;
	F = 7;
	Cl = 7;
	Br = 7;
	I = 7;
*/



	printf("What is the structure of the Lewis Structure?\n\n");
	printf("1 - Tetrahedral\n\n");
	printf("Input corresponding number: ");
	gets (charselect);
	select = atoi(charselect);

	if (select == 1)
	{
		printf("You selected Tetrahedral.\n\n");
		printf("What is the center Element? \n");
		scanf("%s",centerelement);
		printf("What is the 1st periferal element? \n");
		scanf("%s",pelement1);
		printf("What is the 2nd periferal element? \n");
		scanf("%s",pelement2);
		printf("What is the 3rd periferal element? \n");
		scanf("%s",pelement3);
		printf("What is the 4th periferal element? \n");
		scanf("%s",pelement4);

		if(centerelement=="B")
		{
			VEC = 3;
			printf("%d",VEC);
		}

		printf("%s %s %s %s %s", centerelement, pelement1, pelement1, pelement1, pelement1);
	}
}

You can't compare strings with the == operator. Try using strcmp. It returns 0 when the strings are identical.

First off...stop using gets()! It's insecure; view the FAQ here for why and how to fix it.

Secondly, make charselect a single char variable, rather than an array of length 1 (which is wrong, because then there's no room for the required null terminator).

Example code:

Code:

#include <stdio.h>

int main(void)
{
   char selection;
   int c = 0;
   printf("1 - Tetrahedral\n");
   printf("Select one: ");
   while (scanf("%c", &selection) != 1) {
      while((c = getchar()) != '\n') ; /* Consume any leftover chars in the buffer */
      printf("Invalid selection!\nSelect one: ");
   }
   while((c = getchar()) != '\n') ; /* Consume any leftover chars in the buffer */
   if (selection == '1') {
      printf("You selected %c\n", selection);
   } else {
      printf("You selected %c, which is invalid!\n", selection);
   }
   return 0;
}