在 C 中使用 scanf() 时如何忽略某些扫描调用？ （阅读正文）

Question

如果标题有误导性，我深表歉意，因为我不知道从哪里或如何开始。

最近我写了一个数学游戏，可以生成随机数并将它们转换为方程式。但是，如果我想让show-stats 之类的命令显示您的统计数据，程序所能做的就是接受数字。我必须编写命令，然后在后面输入一个数字才能让命令像这样被识别

show-stats 0
score is 1

show-stats
0             //number is required for some reason
score is 1

这是我写的一个小例子

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

int main() {
 int bar;
 char foo[]="";
 int score = 1;
    
 scanf("%s%i",foo,&bar);
 if(strcmp(foo,"show-stats"))
 {
  printf("Score is %i",score);
 }
 
 if(bar == 2)
 {
  score = bar*2;
  printf("Doubled Points.\n");
 }
}

这是实际代码，以备不时之需。另外，我想要关于实际代码的顾问，比如它的意大利面或某些东西是否消耗性能，或者如果它不是太麻烦的话，我一般可以改进什么。在此先感谢，我愿意接受建议。

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>

#define VER 10
#define DIV "-----"

int main()
{
 system("clear");
 
 unsigned int x,y;                                                                                                                                                                   //equation numbers
 int ans,sum;                                                                                                                                                                        //user answer
 unsigned int max = 10;                                                                                                                                                              //max possible number that can be made, cannot go under 10.
 int score;                                                                                                                                                                          //what do you think?
 char operation;
 int correctAnswers = 0,wrongAnswers = 0;

 printf("Math game\nVersion %i.\n",VER);
 for (; ;)
 {
   //phase 1; make numbers.
   srand(time(NULL));
   x = rand() % max;
   y = rand() % max;
   //phase 2; make operation type.
   operation = rand() % 2;
   switch (operation)
   {
    case 0:operation = '+';sum = x + y;break;
    case 1:operation = '-';sum = x - y;break;
   }
   //phase 3; write question to console and get user answer
   printf("What is %i %c %i? ",x,operation,y);                                                                                                                                       //get input
   scanf("%i",&ans);
   //phase 4; determine right answer
   if (ans == sum)
   {
    score++;
    correctAnswers++;
    max++;
    printf("Your correct! +1!\n");
    printf("%sStats%s\nScore:%i\nMax possible number:%i\nCorrect Answers:%i\nWrong Answers:%i\n%s%s%s\n",DIV,DIV,score,max,correctAnswers,wrongAnswers,DIV,DIV,DIV);                   //print stats when user wins,is a seperate call for readability. same thing on line 53 but for loss
   }
   
   else
   {
    score--;
    wrongAnswers++;
    if(max>10){max--;};                                                                                                                                                              //assures max doesn't go under 10
    printf("Wrong! -1\n");
    printf("%sStats%s\nThe correct answer was %i\nMax possible number : %i\nScore : %i\nCorrect Answers : %i\nWrong Answers : %i\n%s%s%s\n",DIV,DIV,sum,max,score,correctAnswers,wrongAnswers,DIV,DIV,DIV);
   }
 }
}

Answer 1

感谢 DevSolar，我知道该怎么做。使用fgets() 和strtol() 您可以收集整个字符串，并将其解析为命令和数字，我在这里阅读了strtol https://www.tutorialspoint.com/c_standard_library/c_function_strtol.htm

编辑：

char str[30] = ""; //the string the user types
   fgets(str,30,stdin);
   char *ptr; //the part of the string turned into words
   long ret; //the part of the string turned into numbers

   ret = strtol(str, &ptr, 10); //parameter 1;source string that is parsed;//parameter 2; string part of source.//parameter 3; base
   printf("The number(unsigned long integer) is %ld\n", ret);
   printf("String part is |%s|", ptr);