Right Triangle Program

Hello to all. Hope everyone is having a good night. I am turning to the message board because I don't know what any of these error messages mean. Hopefully someone out there can help. This program is supposed to calculate the area of a triangle and tell if it is a right triangle or not. Any help is always appreciated.
John

Can anyone help me out or point me in the right direction.

Calculate area of a triangle and tell if its a right triangle or not using a switch
statement. I am getting error messages on lines
righttriangle.c:45: error: expected expression before âelseâ
righttriangle.c:57: error: expected expression before âelseâ
righttriangle.c:126:9: warning: multi-character character constant
righttriangle.c: In function âcalAreaâ:
righttriangle.c:175: error: âfâ undeclared (first use in this function)
righttriangle.c:175: error: (Each undeclared identifier is reported only once
righttriangle.c:175: error: for each function it appears in.)
righttriangle.c:175: error: expected â;â before â}â token
righttriangle.c: In function âmainâ:
righttriangle.c:175: error: expected declaration or statement at end of input
righttriangle.c:175: error: expected declaration or statement at end of input
righttriangle.c:24: warning: unused variable âhypotenuseâ
righttriangle.c: In function âcalLeg1â:
righttriangle.c:161: warning: control reaches end of non-void function
righttriangle.c: In function âcalLeg2â:
righttriangle.c:166: warning: control reaches end of non-void function
righttriangle.c: In function âcalHypotenuseâ:
righttriangle.c:171: warning: control reaches end of non-void function
righttriangle.c: In function âcalAreaâ:
righttriangle.c:175: warning: control reaches end of non-void function
righttriangle.c: In function âmainâ:
righttriangle.c:175: warning: control reaches end of

Code:

 10 #include <stdio.h>
 11 #include <math.h>
 12 
 13 /* Function Prototypes */
 14 void printMenu();
 15 void float calLeg1(float leg2, float hypotenuse);
 16 
 17 void float calLeg2(float leg1, float hypotenuse);
 18 void float calHypotenuse(float leg1, float leg2);
 19 void float calArea(float leg1, float leg2);
 20 
 21 /* Main Function */
 22 int main()
 23 {       
 24         /* InitIalizers for legs and hypotenuse */ 
 25         float leg1 = -1.0, leg2 = -1.0, hypotenuse = -1.0;
 26         
 27         /* Sentinal Controlled loop initializers */
 28         int selection = 0;
 29         int EXIT_VAL = 10;
 30         
 31         /* Beginning of sentinal controlled loop */
 32         while(selection != EXIT_VAL)
 33         {       
 34                 /* Print Menu first */
 35                 printMenu();
 36                 scanf("%d", &selection);
 37                 
 38                 /* Switch on menu options */
 39                 switch(selection)
 40                 {
 41                         /* Input leg1 */
 42                         case '1':
 43                         {printf( "Enter leg1:");
 44                         scanf( "%f",&leg1 );
 45                         if ( leg1 > 0)
 46                         else printf( "Please enter a positive value for leg1\n");
 47                                 /* Did they enter a positive number? */
 48 
 49                                 break;
 50                         }
 51 
 52                         /* Input leg2 */
 53                         case '2':
 54                         {printf( "Enter leg2:");
 55                         scanf( "%f",&leg2 );
 56 
 57                         if ( leg2 > 0)
 58                         else printf("Please enter a positive number:";
 59                                 /* Did they enter a positive number? */
 60                                 break;
 61                         }
 62 
 63                         /* Input hypotenuse */
 64                         case '3':
 65                         {printf( "Enter hypotenuse:");
 66                         scanf( "%f",&hypotenuse );
 67                         if ( hypotenuse > 0)
 68                         printf( "Please enter a positive value for the hypotenuse\n");
 69                                 /* Did they enter a positive number? */
 70                                 break;
 71                         }
 72 
 73                         /* Calculate leg1 */
 74                         case '4':
 75                         {
 76                                 /* If enough values have been inputed to solve for it */
 77                          if leg1 = calLeg1(leg2, hypotenuse)
 78                          else printf("Not enough information:");
 79 
 80 
 81                                 break;
 82                         }
 83 
 84                         /* Calculate leg2 */
 85                         case '5':
 86                         {
 87                                 /* If enough values have been inputed to solve for it */
 88                         if leg2 = calLeg2(leg1, hypotenuse
 89                         else printf("Print need more information:");
 90                                 break;
 91                         }
 92 
 93                         /* Calculate hypotenuse */
 94                         case '6':
 95                         {
 96                                 /* If enough values have been inputed to solve for it */
 97                                 if hypotenuse = calHypotenuse(leg1, leg2)
 98                                 else printf("Need more information:");
 99                                 break;
100                         }
101 
102                         /* Calculate area and print */
103                         case '7':
104                         { area = ( leg1 * leg2 )/2;
105                         printf("The area is %f\n",area);
106                                 /* If enough values have been inputed to solve for it
107                                  * a little more complexe than the other calculates    */
108                                 break;
109                         }
110 
111                         /* Determine if values are a right triangle or not */
112                         case '8':
113                         { if ( leg 1 * leg1 ) + (leg2 * leg2) = ( hypotenuse * hypotenuse )
114                         printf("This is a right triangle\n");
115                         else printf("This is not a right triangle\n");
116                                 /* Make sure you handle all possible cases */
117                                 break;
118                         }
119 
120                         case '9':
121                         {printf( "The values are %f\n%f\n%f",leg1,leg2,hypotenuse);
122                                 /* Display current values for leg1, leg2, and hypotenuse */
123                                 break;
124                         }
125 
126                         /* Exit Case */
127                         case '10':
128                         {
129                                 break;
130                         }
131 
132                         /* If invalid value entered */
133                         default:
134                         {
135                                 printf("Invalid Value entered please select again!\n");
136                         }
137                 }
 138         return 0;
139 }
140 
141 /* Menu Printing Function */
142 void printMenu()
143 {
144 /* Do work for menu
145  * 1.  Input value for leg1
146  * 2.  Input value for leg2
147  * 3.  Input value for hypotenuse
148  * 4.  Calculate leg1
149  * 5.  Calculate leg2
150  * 6.  Calculate hypotenuse
151  * 7.  Calculate area of right triangle
152  * 8.  State if values entered is a real right triangle
153  * 9.  Display current values of leg1, leg2, and hypotenuse
154  * 10. Exit */
155 }
156 
157 
158  float calLeg1(float leg2, float hypotenuse)
159 {
160         /* Calculate value for leg1 and return it */
161 }
162 
163  float calLeg2(float leg1, float hypotenuse)
164 {
165         /* Calculate value for leg2 and return it */
166 }
167 
168  float calHypotenuse(float leg1, float leg2)
169 {
170         /* Calculate value for hypotenuse and return it */
171 }
172 
173  float calArea(float leg1, float leg2)
174 {
175         /* Calculate area for triangle and return it */f}

They all mean what they say:

righttriangle.c:45: error: expected expression before âelseâ

You have to do something, anything, between the if (test) and the else.

righttriangle.c:126:9: warning: multi-character character constant

Characters, that is, things inside 'single quotes', can only be ... a character. So you can try to do '10', but that doesn't mean anything, because '10' is not a single character. You (apparently) want to be using integers anyway, so lose the quotes.

righttriangle.c:175: error: âfâ undeclared (first use in this function)

You've got an "f" sticking out at the end of your last comment. And a ")". And then the compiler complains, because you told it you were defining a function "calArea", but didn't do so.

But I am doing something in line 45 I am saying if leg > 1 move onto the next case if its not print please enter a postive value.

Or atleast that's what I am trying to say.

Then you have your test backwards. Test for < 0, and don't have an else.

(If you absolutely positively for whatever reason (which is probably not good) simply must have a "move on" statement, then you need to put in a do-nothing statement:

Code:

; //do nothing

But usually this means "Hey you coded your test backwards.")

Code:

case 1:
   printf("Enter leg1:");
   if (1 != scanf("%f", &leg1) || 0 >= leg1)
   {
      /* A valid entry was not provided */
      printf("ERROR: A positive value was not entered for leg1\n");
   }
   break;

area is undeclared! That means I need to declare it in main on line 105

What does control reaches end of non void function mean?

Originally Posted by BSmith4740

area is undeclared! That means I need to declare it in main on line 105

What? I guess looking back that is true -- you need to declare that variable before you use it.

Also, just skimming, you're missing a close parenthesis in your calculate leg-2 case; and I would guess you're missing some close braces due to all the "end of input reached" messages you get too.

What does this to do with c#?