Update resistormaid.c

Makefile

@@ -1,5 +1,6 @@
 CC=gcc
-CFLAGS=-Wall -O2
+CFLAGS=-Wall -Wextra -Wpedantic -O2 -std=c99
+LDFLAGS=-lm
 
 ifndef VERBOSE
 .SILENT:
@@ -7,7 +8,8 @@ endif
 
 all: clean resistormaid
 
-resistormaid: resistormaid.o
+resistormaid: resistormaid.c
+	$(CC) $(CFLAGS) resistormaid.c -o resistormaid $(LDFLAGS)
 
 clean:
 	rm -f resistormaid *.o

resistormaid.c

@@ -1,13 +1,16 @@
 #include <stdio.h>
+#include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 #include <ctype.h>
+#include <math.h>
 
 int16_t value = 0;
-float tolerance = 20;
-int8_t multiplier = 0;
 int16_t sixDigit = 0;
+float tolerance = 20;
+float multiplier = 0;
 int8_t hasThirdValueBand = 0;
+int8_t k,m,g = 0;
 
 int colorValues(char *colorInput) {
     if(!strcmp(colorInput, "black"))          return 0;
@@ -73,6 +76,7 @@ int main(int argc, char **argv) {
         goto exit;
     }
     value = firstDigit * 10 + secondDigit; // handles argv[1] and argv[2]
+
     if(numargs > 4) {
         hasThirdValueBand = 1;
         int8_t thirdDigit = colorValues(argv[3]); // handles argv[3]
@@ -90,7 +94,7 @@ int main(int argc, char **argv) {
         goto exit;
         }
 
-    if(numargs > 3) { // handles argv[5]
+    if(numargs > 3) { // handles argv[4] and argv[5]
         tolerance = toleranceValues(argv[4 + hasThirdValueBand]);
         if(tolerance == -1) {
             if(hasThirdValueBand) printf("Invalid fifth argument! Exiting now.\n");
@@ -99,6 +103,22 @@ int main(int argc, char **argv) {
         }
     }
 
+    multiplier = pow(10.0, multiplier);
+    float output = value * multiplier;
+
+    if(output >= 1000.0) {
+        k = 1;
+        output = output / 1000;
+    }
+    if(output >= 1000.0) {
+        m = 1;
+        output = output / 1000;
+    }
+    if(output >= 1000.0) {
+        g = 1;
+        output = output / 1000;
+    }
+
     if(numargs > 5) { // handles argv[6]
         if(!strcmp(argv[6], "black"))       sixDigit = 250;
         else if(!strcmp(argv[6], "brown"))  sixDigit = 100;
@@ -116,8 +136,23 @@ int main(int argc, char **argv) {
             goto exit;
         }
     }
+    char stringOut[16];  // remove the unnecessary '.' and '0' characters
+    sprintf(stringOut, "%.2f", output);
+    int8_t counter = strlen(stringOut) - 1;
+    int8_t exitTracker = 0;
+    while(stringOut[counter] == '0' || stringOut[counter] == '.') {
+        if(stringOut[counter] == '.') exitTracker = 1; // so we stop after the dot
+        stringOut[counter] = '\0';
+        counter--;
+        if(exitTracker) break;
+    }
 
-    printf("%i 10^%i +-%g%%", value, multiplier, tolerance);
+    printf("%s", stringOut);
+    if(g) printf("G");
+    else if(m) printf("M");
+    else if(k) printf("K");
+
+    printf(" Ohm +-%g%%", tolerance);
     if(sixDigit != 0) printf(" %ippm", sixDigit);
     printf("\n");
     exit: