Chapter 4 exercises and exercises in C language programming

[Exercise for 4-1]
0.0000; The while LOOP statement cannot be used. Yes; the number of cycles is reduced.
[Practice 4-2]
Not changed. 0.00; if the negative number does not meet the conditions of the loop statement, the statement jumps out.
[Exercise 4-3]
# Include <stdio. h>
Int main (void)
{
Int flag, denominator;
Double eps, item, s;
Printf ("Enter eps :");
Scanf ("% lf", & eps );
Flag = 1;
S = 0;
Denominator = 1;
Item = 1;
While (item> = eps)
{
S = s + flag * item;
Denominator = denominator + 3;
Item = 1/denominator;
Flag =-flag;
}
S = s + flag * item;
Printf ("s = %. 2f \ n", s );
Return 0;
}
[Exercise 4-4]
# Include <stdio. h>
Int main (void)
{
Int grade, count;
Double sum;
Printf ("Enter grades :");
Scanf ("% d", & grade );
Sum = 0;
Count = 0;
While (grade> = 0)
{
Sum = sum + grade;
Count ++;
Scanf ("% d", & grade );
}
If (count! = 0)
{
Printf ("The average is %. 2f \ n", sum/count );
}
Else
{
Printf ("The average is 0 \ n ");
}
Return 0;
}
[Practice 4-5]
Yes; the loop statement will be executed once more. Add "if (number = 0) break;" at the end of the while statement ;".
[Exercise 4-6]
No. The statement is printed repeatedly.
[Exercise 4-7]
# Include <stdio. h>
Int main (void)
{
Int I, j, n, m;
Printf ("Enter n :");
Scanf ("% d", & n );
For (I = 1; I <= n; I ++)
{
Printf ("Enter # % d number:", I );
Scanf ("% d", & m );
For (j = 2; j <= m/2; j ++)
{
If (m % j = 0)
{
Break;
}
}
If (j> m/2)
{
Printf ("% d is prime number. \ n", m );
}
Else
{
Printf ("% d isn't prine number. \ n", m );
}
}
Return 0;
}
[Exercise 4-8]
# Include <stdio. h>
Int main (void)
{
Int I, j, n;
Double item, sum;
Printf ("Enter n :");
Scanf ("% d", & n );
Sum = 0;
For (I = 1; I <= n; I ++)
{
Item = 1;
For (j = 1; j <= I; j ++)
{
Item = item * j;
}
Sum = sum + 1/item;
}
Printf ("e = %. 2f \ n", sum );
Return 0;
}
[Exercise 4-9]
The highest score is the first input score, and an if statement is added.
[Exercise 4-10]
The highest score is the input negative number. Add an if statement.
[Exercise 4-11]
# Include <stdio. h>
Int main (void)
{
Int min, n, I, number;
Printf ("Enter n :");
Scanf ("% d", & n );
Printf ("Enter #1 number :");
Scanf ("% d", & number );
Min = number;
For (I = 2; I <= n; I ++)
{
If (min> number)
{
Min = number;
}
Printf ("Enter # % d number:", I );
Scanf ("% d", & number );
}
Printf ("The min number is % d \ n", min );
Return 0;
}
[Exercise 4-12]
# Include <stdio. h>
Int main (void)
{
Int number, m;
Printf ("Enter a number :");
Scanf ("% d", & number );
If (number <0)
{
Number =-number;
}
Do
{
M = number;
Printf ("% d", m );
Number = number/10;
}
While (number! = 0 );
Printf ("\ n ");
Return 0;
}
[Exercise 4-13]
# Include <stdio. h>
# Include <math. h>
Int main (void)
{
Int I, j, count;
Count = 0;
For (I = 100; I <= 200; I ++)
{
For (j = 2; j <sqrt (I); j ++)
{
If (I % j = 0)
{
Break;
}
}
If (j> sqrt (I ))
{
Printf ("m", I );
Count ++;
}
If (count/8> 0 & count % 8 = 0)
{
Printf ("\ n ");
}
}
Printf ("\ n ");
Return 0;
}
[Exercise 4-14]
# Include <stdio. h>
Int main (void)
{
Int x, x1, x2, I, count;
X1 = 1;
X2 = 1;
Count = 2;
Printf ("mm", x1, x2 );
For (I = 1; I <= 18; I ++)
{
X = x1 + x2;
Printf ("m", x );
Count ++;
X1 = x2;
X2 = x;
If (count/10> 0 & count = 0)
{
Printf ("\ n ");
}
}
Return 0;
}
[Exercise 4-1]
# Include <stdio. h>
Int main (void)
{
Int number, sum;
Printf ("Enter number :");
Scanf ("% d", & number );
Sum = 0;
If (number> 0)
{
While (number % 2 = 0)
{
Sum = sum + number;
Scanf ("% d", & number );
}
Printf ("sum = % d \ n", sum );
}
Return 0;
}
[Exercise 4-2]
# Include <stdio. h>
# Include <math. h>
Int fact (int n );
Int main (void)
{
Int I, j;
Double s, x, item;
Printf ("Enter x :");
Scanf ("% lf", & x );
S = 0;
I = 1;
J = 1;
Item = pow (x, I)/fact (j );
While (fabs (item) & gt; 0.00001)
{
S = s + item;
I ++;
J ++;
Item = pow (x, I)/fact (j );
}
Printf ("s = %. 2f \ n", s );
Return 0;
}
Int fact (int n)
{
Int I, s;
S = 1;
For (I = 1; I <= n; I ++)
{
S = s * I;
}
Return s;
}
[Exercise 4-3]
# Include <stdio. h>
Int main (void)
{
Int number, sum, digit, item;
Printf ("Enter number :");
Scanf ("% d", & number );
Sum = 0;
Digit = 0;
While (number> 0)
{
Item = number;
Sum = sum + item;
Digit ++;
Number = number/10;
}
Printf ("sum = % d, digit = % d \ n", sum, digit );
Return 0;
}
[Exercise 4-4]
# Include <stdio. h>
Int main (void)
{
Int numerator, I, n, x;
Double item, sum, denominator;
Printf ("Enter n :");
Scanf ("% d", & n );
Sum = 0;
Denominator = 1;
Numerator = 2;
For (I = 1; I <= n; I ++)
{
Item = numerator/denominator;
Sum = sum + item;
X = numerator;
Numerator = numerator + denominator;
Denominator = x;
}
Printf ("sum = %. 2f \ n", sum );
Return 0;
}
[Exercise 4-5]
# Include <stdio. h>
Int main (void)
{
Int a, n, I, j, sum, item;
Printf ("Enter :");
Scanf ("% d", & );
Printf ("Enter n :");
Scanf ("% d", & n );
Sum = 0;
Item = 0;
For (I = 1; I <= n; I ++)
{
Item = item * 10 +;
Sum = sum + item;
}
Printf ("s = % d \ n", sum );
Return 0;
}
[Exercise 4-6]
# Include <stdio. h>
Int main (void)
{
Int a, B, c;
For (a = 1; a <= 10; a ++)
{
For (B = 1; B <= 5; B ++)
{
For (c = 1; c <= 2; c ++)
{
If (a + B * 2 + c * 5 = 10)
{
Printf ("1fen = % d, 2fen = % d, 5fen = % d \ n", a, B, c );
}
}
}
}
Return 0;
}
[Exercise 4-7]
# Include <stdio. h>
# Include <math. h>
Int main (void)
{
Int I, m, x, count;
Double sum;
For (I = 1; I <= 10000; I ++)
{
X = I;
Sum = 0;
While (x! = 0)
{
M = x;
Sum = sum + pow (m, 3 );
X = x/10;
}
If (sum = I)
{
Printf ("m", I );
Count ++;
}
If (count> 0 & count % 5 = 0)
{
Printf ("\ n ");
}
}
Printf ("\ n ");
Return 0;
}
[Exercise 4-8]
# Include <stdio. h>
# Include <math. h>
Int main (void)
{
Int I, k, j, l, count, n;
Double m;
For (I = 6; I <= 100; I ++)
{
If (I % 2 = 0)
{
For (j = 2; j <= I/2; j ++)
{
M = sqrt (j );
For (k = 2; k <= m; k ++)
{
If (j % k = 0)
{
Break;
}
}
If (k> m)
{
N = I-j;
If (n> 0)
{
M = sqrt (n );
For (l = 2; l <= m; l ++)
{
If (n % l = 0)
{
Break;
}
}
If (l> m)
{
Printf ("m = % d + % d", I, j, n );
Count ++;
If (count! = 0 & count % 5 = 0)
{
Printf ("\ n ");
}
}
}
}
}
}
}
Printf ("\ n ");
Return 0;
}
[Exercise 4-9]
# Include <stdio. h>
Int main (void)
{
Int n, a, B, c;
Printf ("Enter number :");
Scanf ("% d", & n );
B = 0;
While (n! = 0)
{
B = B * 10;
A = n;
N = n/10;
B = B +;
}
While (B! = 0)
{
C = B;
Printf ("=", c );
B = B/10;
}
Printf ("\ n ");
Return 0;
}
[Exercise 4-10]
# Include <stdio. h>
Int main (void)
{
Int n, I, m;
Printf ("Enter number :");
Scanf ("% d", & n );
Printf ("% d =", n );
M = n/2;
For (I = 2; I <= m; I ++)
{
If (n % I = 0)
{
Printf ("% d", I );
N = n/I;
Break;
}
}
While (n> 1)
{
For (I = 2; I <= m; I ++)
{
If (n % I = 0)
{
Printf ("* % d", I );
N = n/I;
Break;
}
}
}
Printf (". \ n ");
Return 0;
}
[Exercise 4-11]
# Include <stdio. h>
Int main (void)
{
Int m, n, k, l, max, min, I;
Printf ("Enter m :");
Scanf ("% d", & m );
Printf ("Enter n :");
Scanf ("% d", & n );
Max = 1;
Min = m * n;
L = m * n;
If (m> n)
{
K = m;
}
Else
{
K = n;
}
For (I = 2; I <= k; I ++)
{
If (m % I = 0 & n % I = 0)
{
If (I> max)
{
Max = I;
}
}
}
For (I = 2; I <= min; I ++)
{
If (min % I = 0)
{
If (m % I = 0 & n % I = 0)
{
L = min/I;
If (l <min)
{
Min = l;
}
}
}
}
Printf ("max = % d, min = % d \ n", max, min );
Return 0;
}
[Exercise 4-12]
# Include <stdio. h>
Int main (void)
{
Int I;
Double n, sum;
Sums = 100;
N = 100;
For (I = 2; I <= 10; I ++)
{
Sum = sum + n;
N = n/2;
}
Printf ("sum = %. 4f, high = %. 4f \ n", sum, n );
Return 0;
}
[Exercise 4-13]
# Include <stdio. h>
Int main (void)
{
Int I, j, k;
For (I = 1; I <= 4; I ++)
{
For (j = 1; j <(5-i); j ++)
{
Printf ("");
}
J = 2 * I-1;
For (k = 1; k <= j; k ++)
{
Printf ("*");
}
Printf ("\ n ");
}
For (I = 3; I> = 1; I --)
{
For (j = 1; j <(5-i); j ++)
{
Printf ("");
}
J = 2 * I-1;
For (k = 1; k <= j; k ++)
{
Printf ("*");
}
Printf ("\ n ");
}
Return 0;
}
[Exercise 4-14]
# Include <stdio. h>
Int main (void)
{
Int I, n;
N = 1;
For (I = 1; I <= 9; I ++)
{
N = (n + 1) * 2;
}
Printf ("n = % d \ n", n );
Return 0;
}