C language code record

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Chinese questions （ Class B ）

1001

#include <stdio.h>

int main() {
    
	int n, cnt;
	cnt = 0;
	scanf("%d", &n);
	while (n != 1) {
    
		if (n % 2 == 1) {
    
			n = (3 * n + 1) / 2;
		} else {
    
			n = n / 2;
		}
		cnt ++;
	}
	printf("%d", cnt);
	return 0;
}

1002

Law 1 ：

#include <stdio.h>
#include <string.h>

int main() {
    
	int sum, i;
	sum = 0;
	i = 0;
	int re[5];
	char a[200], s[20][10];
	strcpy(s[0], "ling");
	strcpy(s[1], "yi");
	strcpy(s[2], "er");
	strcpy(s[3], "san");
	strcpy(s[4], "si");
	strcpy(s[5], "wu");
	strcpy(s[6], "liu");
	strcpy(s[7], "qi");
	strcpy(s[8], "ba");
	strcpy(s[9], "jiu");
	scanf("%s", a);
	while (a[i] != '\0') {
    
// printf("%c\n", a[i]);
		sum = sum + (a[i] - '0');
		i++;
	}
// printf("sum:%d\n", sum);
	re[0] = sum / 100;
	sum = sum % 100;
	re[1] = sum / 10;
	sum = sum % 10;
	re[2] = sum;
// printf(" Three figures :%d %d %d\n", re[0], re[1], re[2]);
	if (re[0] != 0) {
    
		printf("%s %s %s", s[re[0]], s[re[1]], s[re[2]]);
	} else {
    
		if (re[1] != 0) {
    
			printf("%s %s", s[re[1]], s[re[2]]);
		} else {
    
			printf("%s", s[re[2]]);
		}
	}
	return 0;
}

$【pit】$ Character array definition
How to assign values to this array ？
1、 When defining, directly assign values with strings
char a[10]=“hello”;
Be careful ： You can't define it before assigning it a value , Such as char a[10]; a[10]=“hello”; This is wrong ！
2、 Assign values to the characters in the array one by one
char a[10]={‘h’,‘e’,‘l’,‘l’,‘o’};
3、 utilize strcpy
char a[10]; strcpy(a, “hello”);
$easywronglovecondition：$
1、char a[10]; a[10]=“hello”;// How can a character hold a string ？ Besides, a[10] There is no such thing as ！
2、char a[10]; a=“hello”;// This is easy to happen ,a Although it's a pointer , But it already points to the... Allocated in the stack 10 Character space , Now this situation a And points to... In the data area hello Constant , The pointer here a There's chaos , Don't allow ！
also ： Cannot use relational operator “＝＝” To compare two strings , Only use strcmp() Function to handle .

Law two ：

#include <stdio.h>
#include <string.h>

int main() {
    
	// Read in characters and numbers 
	char input[105];
	int len, i, sum;
	sum = 0;
	scanf("%s", input);
	// Calculate the sum of the numbers 
	len = strlen(input);
	for (i = 0; i < len; i++) {
    
		sum += input[i] - '0';
	}
	// Chinese Pinyin 
	char change[15][6] = {
    "ling", "yi", "er", "san", "si", "wu", "liu", "qi", "ba", "jiu"};
	int a[5];
	i = 0;
	while (sum != 0) {
    
		a[i] = sum % 10;	//a[i]i=0 It's a bit 
		sum = sum / 10;
		i++;
	}
	int j;
	for (j = i - 1; j > 0; j--) {
    
		printf("%s ", change[a[j]]);
	}
	printf("%s", change[a[0]]);
	return 0;
}

Method 1 calculates the sum of bits in the case of position character length
Method 2 uses the function of character length to calculate the sum of the number of characters
Method 2: copy the character array , Directly assign values when defining

1003

#include <stdio.h>
#include <string.h>

int main() {
    
	int n, i, j, flag;
	char str[105];
	scanf("%d", &n);
	getchar();
	int p, a, t;
	int x, y, z, len;
	for (i = 0; i < n; i++) {
    
		p = t = 0;
		flag = 1;
		x = y = z = 0;
		str[0] = '\0';
		gets(str);
		len = strlen(str);
		for (j = 0; j < len; j++) {
    
			if (str[j] != 'P' && str[j] != 'A' && str[j] != 'T') {
    
				if (i != n - 1) {
    
					printf("NO\n");
				} else
					printf("NO");
				flag = 0;
				break;
			}
		}
		if (flag == 1) {
    
			for (j = 0; j < len; j++) {
    
				if (str[j] == 'P') {
    
					x = j; //p Prior to j individual a
					p++;
				}
				if (str[j] == 'T') {
    
					y = j - x - 1;
					t++;
				}
			}
			z = len - x - y - 2;
		} else {
    
			continue;
		}

// printf("x:%d y:%d z:%d\n", x, y, z);
		if (z == x * y && p == 1 && t == 1 && y >= 1) {
    
			if (i != n - 1) {
    
				printf("YES\n");
			} else
				printf("YES");
		} else {
    
			if (i != n - 1) {
    
				printf("NO\n");
			} else
				printf("NO");
		}
	}
	return 0;
}