我的第二個函數存根似乎無限循環？

Question

我有兩個相對相同的存根函數，但是當我打電話給第二個存根似乎無限循環，我不知道爲什麼。我在這段無限循環的代碼中調用的函數是convert_weight（）;.我懷疑它是否是主程序問題，因爲它被調用並打印出前幾個printf而沒有問題，但是當使用來自scanf的用戶輸入時，它會進入無限循環。任何幫助將是有用的，請和謝謝。

#include <stdio.h> 
void convert_lengths(int users_choice); 
void convert_weight(int users_choice); 
void length_to_metric(void); 
void length_to_us(void); 
void weight_to_metric(void); 
void weight_to_us(void); 

int main() 
{ 
    int users_choice; 
    do 
    { 
     printf("Do you want to convert length or weights?\n"); 
     printf("1 for length\n"); 
     printf("2 for weights\n"); 
     printf("0 to end program\n"); 
     scanf("%d", &users_choice); 
     if(users_choice == 1) 
     { 
      convert_lengths(users_choice); 
     } 
     if(users_choice == 2) 
     { 
      convert_weight(users_choice); 
     } 
    }while(users_choice != 0); 
    return 0; 
} 
void convert_lengths(int a) 
{ 
    int b; 
    do 
    { 
     if(a == 1) 
     { 
      printf("You have chosen to convert lengths\n"); 
      printf("What units do you want to convert?\n"); 
      printf("- 1 to convert feet/inches to meters/centimeters\n"); 
      printf("- 2 to convert from meters/centimeters to feet/inches\n"); 
      printf("- 0 to go back to other options\n"); 
      scanf("%d", &b); 
      if(b == 1) 
      { 
       printf("You have chosen to convert feet/inches to meters/centinmeters\n\n"); 
       length_to_metric(); 
      } 
      if(b == 2) 
      { 
       printf("You have chosen to convert meters/centimeters to feet/inches\n\n"); 
       length_to_us(); 
      } 
     } 
    }while(b != 0); 
} 
void convert_weight(int a) 
{ 
    int b; 
    do 
    { 

     if(a == 2) 
     { 
      printf("You have chosen to convert weights\n"); 
      printf("What units of weight do you want to convert?\n"); 
      printf("- 1 for pounds/ounces to kilograms/grams\n"); 
      printf("- 2 for kilograms/gram to pounds/ounces\n"); 
      printf("- 0 to go back to other options\n"); 
      scanf("%b", &b); 
      if(b == 1) 
      { 
       printf("You have chosen to convert pounds/ounces to kilograms/gram\n\n"); 
       weight_to_metric(); 

      } 
      if(b == 2) 
      { 
       printf("You have chosen to convert kilograms/gram to pounds/ounces\n\n"); 
       weight_to_us(); 
      } 
     } 

    }while(b != 0); 
} 
void length_to_metric(void) 
{ 
    return; 
} 
void length_to_us(void) 
{ 
    return; 
} 
void weight_to_metric(void) 
{ 
    return; 
} 
void weight_to_us(void) 
{ 
    return; 
} 

Answer 1

您在convert_weight函數中使用了錯誤的格式說明爲scanf：

scanf("%b", &b); 
     ^

它應該是%d，其內容爲一個整數。