加号未读

Question

For some reason my program doesn't read plus sign at all and it doesn't matter if I do it this way:

#include <stdio.h>
#include <math.h>

int main (){

 int nextInt,number,boolean;
 char sign;
 scanf("%d", &number);
 boolean = 1;

 while(boolean == 1){ //+43 *42 %37
   scanf("%c %d", &sign, &nextInt);

   switch ((int)sign){
     case 43:{ number += nextInt; printf("+= %d\n", number); break;}
     case 42:{ number *= nextInt; printf("*= %d\n", number); break;}
     case 37:{ printf("mod %d\n", number);
                number %= nextInt;
                boolean = 0; break;}
   }
 }

 printf("%d", number);
 return 0;
}

Or switch ascii with symbols for switch (sign). I'm kinda clueless what is really the source of the problem right now. What am I doing wrong?

EDIT: Entire code pasted

Answer 1

Since 1806 % 37 = 30, you can verify that the following works.

#include <stdio.h>

int main (){

  int nextInt=0;
  int number=0;
  int boolean;
  char sign;
  boolean = 1;

  while(boolean == 1){ //+43 *42 %37
    scanf(" %c %d", &sign, &nextInt);

    switch (sign){
      case '+':{ number += nextInt; printf("+= %d\n", number); break;}
      case '*':{ number *= nextInt; printf("*= %d\n", number); break;}
      case '%':{ printf("mod %d\n", number);
        number %= nextInt;
        boolean = 0; break;}
    }
  }

  printf("%d", number);
  return 0;
}

The reason your program didn't read plus is that it wasn't in the loop. You can verify that the program works:

+43
+= 43
*42
*= 1806
%37
mod 1806
30
Process finished with exit code 0