.

trivial/CMakeLists.txt

@@ -2,6 +2,7 @@ add_subdirectory(leetcode)
 add_subdirectory(json)
 add_subdirectory(thread_pool)
 add_subdirectory(single)
+add_subdirectory(cprogram)
 
 if(UNIX)
   add_subdirectory(coroutine)

trivial/cprogram/CMakeLists.txt

@@ -0,0 +1,7 @@
+set(EXECUTABLE_OUTPUT_PATH ${OUTPUT_BASE}/cprogram)
+
+link_libraries(m)
+
+add_executable(reverse_words reverse_words.c)
+add_executable(min_common_value min_common_value.c)
+add_executable(bookshop bookshop.c)

trivial/cprogram/README.md

@@ -0,0 +1,3 @@
+# C Program
+
+《C 语言程序设计》课程相关题目

trivial/cprogram/bookshop.c

@@ -0,0 +1,71 @@
+#include <stdio.h>
+#include <string.h>
+
+struct Book {
+  int id;
+  char title[50];
+  char author[50];
+  int price;
+};
+
+struct BookShop {
+  char name[32];
+  struct Book books[100];
+  int nbooks;
+};
+
+int main(int argc, char const* argv[]) {
+  struct BookShop shops[10];
+  int nshops;
+  scanf("%d", &nshops);
+  for (int i = 0; i < nshops; i++) {
+    struct BookShop* shop = &shops[i];
+    scanf("%s", shop->name);
+    scanf("%d", &shop->nbooks);
+    for (int j = 0; j < shop->nbooks; j++) {
+      struct Book* book = &shop->books[j];
+      scanf("%d", &book->id);
+      scanf("%s", book->title);
+      scanf("%s", book->author);
+      scanf("%d", &book->price);
+    }
+  }
+
+  // input an author name, find all the books written by the author, and print the
+  // shop name, book title, and price of each book
+  char author[50];
+  scanf("%s", author);
+  for (int i = 0; i < nshops; i++) {
+    struct BookShop* shop = &shops[i];
+    for (int j = 0; j < shop->nbooks; j++) {
+      struct Book* book = &shop->books[j];
+      if (strcmp(book->author, author) == 0) {
+        printf("%s %s %d\n", shop->name, book->title, book->price);
+      }
+    }
+  }
+
+  return 0;
+}
+
+/*give an example input
+
+3
+shop1
+3
+1 book1 author1 105
+2 book2 author1 520
+3 book3 author2 200
+shop2
+2
+4 book4 author1 350
+5 book5 author2 240
+shop3
+4
+6 book6 author3 230
+7 book7 author4 380
+8 book8 author1 105
+9 book9 author5 260
+author1
+
+*/

trivial/cprogram/min_common_value.c

@@ -0,0 +1,41 @@
+#include <stdio.h>
+#define INT_MAX 1000000
+
+int main(int argc, char const* argv[]) {
+  int n1, n2;
+  int arr1[50], arr2[50];
+
+  scanf("%d %d", &n1, &n2);
+  for (int i = 0; i < n1; i++) {
+    scanf("%d", &arr1[i]);
+  }
+  for (int i = 0; i < n2; i++) {
+    scanf("%d", &arr2[i]);
+  }
+
+  int* ptr1 = arr1;
+  int* ptr2 = arr2;
+
+  int min = INT_MAX;
+
+  while (ptr1 < arr1 + n1) {
+    while (ptr2 < arr2 + n2) {
+      if (*ptr1 == *ptr2) {
+        if (*ptr1 < min) {
+          min = *ptr1;
+        }
+      }
+      ptr2++;
+    }
+    ptr2 = arr2;
+    ptr1++;
+  }
+
+  if (min == INT_MAX) {
+    printf("-1\n");
+  } else {
+    printf("%d\n", min);
+  }
+
+  return 0;
+}

trivial/cprogram/reverse_words.c

@@ -0,0 +1,68 @@
+/**
+ * Reverse the words in a string using pointer
+ *
+ * Example:
+ *  Input: "Hello World"
+ *  Output: "World Hello"
+ */
+#include <stdio.h>
+#include <string.h>
+
+void simplify(char* str) {
+  char* p1 = str;
+  char* p2 = str;
+  int n = 0;
+
+  while (*p2) {
+    if (*p2 == ' ' && (n == 0 || *(p2 + 1) == ' ' || *(p2 + 1) == '\0')) {
+      p2++;
+    } else {
+      *p1 = *p2;
+      p1++;
+      p2++;
+      n++;
+    }
+  }
+
+  *p1 = '\0';
+}
+
+void reverse(char* start, char* end) {
+  char temp;
+  while (start < end) {
+    temp = *start;
+    *start = *end;
+    *end = temp;
+    start++;
+    end--;
+  }
+}
+
+int main(int argc, char const* argv[]) {
+  char str[100];
+  scanf("%[^\n]", str);
+
+  simplify(str);
+
+  reverse(str, str + strlen(str) - 1);
+
+  char* start = str;
+  char* end = str;
+
+  while (*end) {
+    if (*(end + 1) == '\0') {
+      reverse(start, end);
+    } else if (*end == ' ') {
+      reverse(start, end - 1);
+      while (*(end + 1) && *(end + 1) == ' ') {
+        end++;
+      }
+      start = end + 1;
+    }
+    end++;
+  }
+
+  printf("%s\n", str);
+
+  return 0;
+}