Chapter 3 Review. /* Program 3.2, Page 31 with additional code to practice arithmetic operations */ #include <stdio.h> int main (void) {

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1 Chapter 3 Review Data Types, Variables, Arithmetic Operators, Precedence Next to each print statement in the program below, write what will be printed. /* Program 3.2, Page 31 with additional code to practice arithmetic operations */ int main (void) { // declaring some variables int a = 100, b=2, c=25, d=4, e=1; int result; result = a b; printf ( a b = %i \n, result); a b = 98 result = b * c; printf ( b * c = %i \n, result); b * c = 50 result = a / c; printf ( a / c = %i \n, result); a / c = 4 result = a + b * c; printf ( a + b * c = %i \n, result); a + b * c = 150 printf ( a * b + c * d = %i \n, a * b + c * d); a * b + c * d = 300 printf ( -a = %i \n, -a); -a = -100 printf ( a %% b = %i \n, a % b); a % b = 0 printf ( c %% d = %i \n, c % d); c % d = 1 printf ( a = %i \n, a); a = 100 printf ( a /= d + e makes a = %i \n, a /= d + e); a /= d + e makes a = 20 printf ( a = %i \n, a); a = 20 printf ( b +=5 makes b = %i \n, b += 5); b +=5 makes b = 7 printf("25 / 2 = %i (using %%i)\n", 25 / 2); 25 / 2 = 12 (using %i) printf("25 / 2 = %f (using %%f)\n", (foat)25 / 2); // add this cast to compile 25 / 2 = (using %f) printf("(float) 25 / 2 = %f (using %%f) \n", (float) 25 / 2); (float) 25 / 2 = (using %f) printf("25.0 / 2 = %i (using %%i)\n", (int)25.0 / 2); // add this cast to compile 25.0 / 2 = 12 (using %i) printf("(int) 25.0 / 2 = %i (using %%i)\n", (int) 25.0 / 2); (int) 25.0 / 2 = 12 (using %i) printf("25.0 / 2 = %f (using %%f)\n\n", 25.0 / 2); 25.0 / 2 = (using %f)

2 Integer Size and Range /* playing around with large integers */ int main(void) { /* NEGATIVE VALUE */ /* int type is a signed value by default the range is from to so what happens when it's out of range?? */ COMPILE WARNING: review2.c:11:4: warning: overflow in implicit constant conversion [-Woverflow] int largeint1 = ; ^ int largeint1 = ; printf("\n\nlargeint1 (int) is %i\n\n", largeint1); OUTPUT: largeint1 (int) is // make it a long int and it will be big enough to hold this value long int largeint2 = ; printf("\n\nlargeint2 (long int) is %li\n\n", largeint2); largeint2 (long int) is /* POSITIVE VALUE */ // out of range again for signed int int largeint3 = ; printf("\n\nlargeint3 (int) is %i\n\n", largeint3); largeint3 (int) is /* making it unsigned changes the range from 0 to so now it can hold this value */ unsigned int largeint4 = ; printf("\n\nlargeint4 (unsigned int) is %u\n\n", largeint4); largeint4 (unsigned int) is /* when declaring a long int you can the type from long int to just long */ long largeint5 = ; printf("\n\nlargeint5 (long) is %li\n\n", largeint5); largeint5 (long) is

3 Assignments What is another way of writing the following? a += 10; a = a + 10; b -= 5; b = b 5; c /= 6; c = c / 6; Which of the following is the same as: a *= b + c; a = a * b + c; OR a = a * (b + c); More Practice with Precedence What will be the value of result for each of the following if x = 3 and y = 9: result = x + 5 * y / 3 * x; 48 result = x + ((5 * y) / (3 * x)); 8 result = x + (5 * (y / 3)) * x; 48 result = ((x + 5) * y) / (3 * x); 8

4 Issues with Division /* division examples */ int main(void) { int a = 10, b = 4, c = 0; float f; f = a / b; // what to do to fix this truncation???? cast float to either a or b printf("%.2f \n\n", f); printf("%i \n\n", a / c); // what's the problem with this???? It is dividing by 0. Compiler does not pick that up it s a run- time error. It will give you a floating point exception when run. Unary Minus Operator Show what will be printed out by the print statement below: int a = 15, b; b = -a; printf( a is %d and b is %d \n, a, b); a is 15 and b is -15

5 Increment & Decrement Operators Show what will be printed out by the print statements below: int a = 10, b; b = a--; printf( a is %d and b is %d \n, a, b); a is 9 and b is 10 int a = 10, b; b = --a; printf( a is %d and b is %d \n, a, b); a is 9 and b is 9 Full program example: /* increment example */ int main(void) { int a, b; // post-fix increment starting a with the value of 10 b = a++; printf("a is %i, b is %i \n\n", a, b); a is 11 and b is 10 // pre-fix increment starting with a back at 10 again b = ++a; printf("a is %i, b is %i \n\n", a, b); a is 11 and b is 11 // post-fix increment in a mathematical expression // resetting a back to 10 again b = a++ * 10; printf("a is: %i, b is: %i \n\n", a, b); a is 11 and b is 100 // pre-fix increment in a mathematical expression // resetting a back to 10 again b = ++a * 10; printf("a is: %i, b is: %i \n\n", a, b); a is 11 and b is 110

6 Practice with Number Conversions = = = = = A = 9EF = = B38C616 = = = = CA16

7 Printf Statements with Octal, Hex, & ASCII /* This program demonstrates: 1. what an address looks like using %p format string (%p shows the address as a hex value) 2. the hex and octal format codes 3. ASCII code - prints a character using its hex and octal representations */ int main (void) { int x = 12; printf("\nx is %d\n", x); x is 12 printf("address of x is %p\n\n", &x); address of x is 0x7ffc394a674c printf("using %%x with hex code 0x41: %x\n", 0x41); using %x with hex code 0x41: 41 printf("using %%#x with hex code 0x41: %#x\n", 0x41); using %#x with hex code 0x41: 0x41 printf("using %%X with hex code 0x41: %X\n", 0x41); using %X with hex code 0x41: 41 printf("using %%#X with hex code 0x41: %#X\n\n", 0x41); using %#X with hex code 0x41: 0X41 printf("using %%o with octal code 0101: %o\n", 0101); using %o with octal code 0101: 101 printf("using %%#o with octal code 0101: %#o\n\n", 0101); using %#o with octal code 0101: 0101 printf("the letter A (using %%c with decimal code 65): %c\n", 65); the letter A (using %c with decimal code 65): A printf("the letter A (using %%c with hex code 0x41): %c\n", 0x41); the letter A (using %c with hex code 0x41): A printf("the letter A (using %%c with octal code 0101): %c\n\n", 0101); the letter A (using %c with octal code 0101): A // more fun with ASCII code printf("ascii 65 (capital A): %c\n\n", 65); ascii 65 (capital A): A printf("ascii 065 (the number 5): %c\n\n ", 065); // octal notation ascii 065 (the number 5): 5 printf("ascii 1 (non-printable character): %c\n\n ", 1); ascii 1 (non-printable character): printf("ascii 37 (percent sign): %c\n\n ", 37); ascii 37 (percent sign): % printf("ascii 0x2b (plus sign): %c\n\n ", 0x2b); // hexadecimal ascii 0x2b (plus sign): + printf("ascii 057 (forward slash): %c\n \n", 057); // octal ascii 057 (forward slash): / printf("ascii 7 (beep) %c\n", 7); ascii 7 (beep)