C Primer Plus编程练习答案（Chapter6）

6.16.1

#include 
int main() {
	char alphabet[26];
	int i;
	
	for (i = 0; i < 26; i++)
		alphabet[i] = 'a' + i;
	
	for (i = 0; i < 26; i++)
		printf("%c ", alphabet[i]);

	return 0;
}

 6.16.2

#include 
int main() {
	int i, j;
	for (i = 0; i < 5; i++) {
		for (j = 0; j < i + 1; j++)
			printf("$");
		printf("n");
	}
}		

 6.16.3

#include 
int main() {
	int i, j;
	for (i = 0; i < 6; i++) {
		for (j = 0; j < i + 1; j++)
			printf("%c",'F' - j);
		printf("n");
	}
}		

 6.16.4

#include 
int main() {
	int i, j, k = 0;
	for (i = 0; i < 6; i++) {
		for (j = 0; j < i + 1; j++) {
			printf("%c", 'A' + k);
			k++;
		}
		printf("n");
	}
}		

 6.11.5

#include 
int main() {
	int i, j, k;
	char letter;

	printf("Please enter a captial letter: ");
	scanf_s("%c", &letter);

	for (i = 0; i < letter - 'A' + 1; i++) {
		for (j = 0; j < letter - 'A' - i; j++)
			printf(" ");
		for (k = 0; k < i + 1; k++)
			printf("%c", 'A' + k);
		for (; k - 1 > 0; k--)
			printf("%c", 'A' + k - 2);
		printf("n");
	}
	return 0;
}		

 6.11.6

#include 
int main() {
	int max, min;
	int i, temp;

	printf("请输入表格的上限和下限:");
	scanf_s("%d %d", &max, &min);
	printf("整数    平方    立方   n");

	for (i = 0; i <= max - min; i++) {
		temp = min + i;
		printf("%-7d %-7d %-7dn", temp, temp * temp, temp * temp * temp);
	}

	return 0;
}

 6.11.7

#include 
#include 
int main() {
	char word[20], new_word[20];
	int i, len;

	printf("Please enter a word: ");
	scanf("%s", word);
	len = strlen(word);
	for (i = 0; i < len; i++)
		new_word[i] = word[len - i - 1];
	new_word[i] = '';

	printf("%s", new_word);
}

 6.11.8

#include 
int main() {
	float f1, f2;
	int n;
	printf("Please enter two float number(NaN to quit):");
	n = scanf_s("%f %f", &f1, &f2);
	while (n == 2){
		printf("%.2f n", (f1 - f2) / (f1 * f2));
		printf("Please enter next two float number(NaN to quit):");
		n = scanf_s("%f %f", &f1, &f2);
	}
	printf("byebye.");
	
	return 0;
}

6.11.9 

#include 
float count(float F1, float F2) {
	float result;
	result = (F1 - F2) / (F1 * F2);
	return result;
}
int main() {
	float f1, f2;
	int n;
	printf("Please enter two float number(NaN to quit):");
	n = scanf_s("%f %f", &f1, &f2);
	while (n == 2){
		printf("%.2f n", count(f1,f2));
		printf("Please enter next two float number(NaN to quit):");
		n = scanf_s("%f %f", &f1, &f2);
	}
	printf("byebye.");
	
	return 0;
}

 6.11.10

#include 
int main() {
	int max, min;
	int i, sum = 0;
	printf("Enter lower and upper integer limits: ");
	scanf_s("%d %d", &min, &max);

	while (min < max) {
		sum = 0;
		for (i = 0; i < max - min + 1; i++)
			sum += (min + i) * (min + i);
		printf("The sums of the square from %d to %d is %dn", min * min, max * max, sum);
		printf("Enter next set of limits: ");
		scanf_s("%d %d", &min, &max);
	}
	printf("Done.");
	return 0;

}

 6.16.11

#include 
#define SIZE 8
int main() {
	int array[SIZE];
	int i;
	
	printf("Please enter %d numbers: ", SIZE);
	for (i = 0; i < SIZE; i++)
		scanf_s("%d", &array[i]);

	for (i = 0; i < SIZE; i++)
		printf("%d ", array[SIZE - i - 1]);
	
	return 0;
}