fork(1) download 
  1. #include <stdio.h>
  2. #include <stdint.h>
  3.  
  4. unsigned long long divisors[] = {
  5.   1000000000,
  6.   1000000000,
  7.   1000000000,
  8.   1000000000,
  9.   100000000,
  10.   100000000,
  11.   100000000,
  12.   10000000,
  13.   10000000,
  14.   10000000,
  15.   1000000,
  16.   1000000,
  17.   1000000,
  18.   1000000,
  19.   100000,
  20.   100000,
  21.   100000,
  22.   10000,
  23.   10000,
  24.   10000,
  25.   1000,
  26.   1000,
  27.   1000,
  28.   1000,
  29.   100,
  30.   100,
  31.   100,
  32.   10,
  33.   10,
  34.   10,
  35.   1,
  36.   1,
  37.   1
  38. };
  39.  
  40.  
  41. int main()
  42. {
  43.   unsigned long long int i, j, res;
  44.  
  45.   unsigned char inbuff[2500000]; /* To be certain there's no overflow here */
  46.   unsigned char *in = inbuff;
  47.   char outbuff[2500000]; /* To be certain there's no overflow here */
  48.   char *out = outbuff;
  49.  
  50.   int c = 0;
  51.  
  52.   while(1) {
  53.     i = j = 0;
  54.  
  55.     inbuff[fread(inbuff, 1, 2500000, stdin)] = '\0';
  56.  
  57.     /* Skip whitespace before first number and check if end of input */
  58.     do {
  59.       c = *(in++);
  60.     } while(c != '\0' && !(c >= '0' && c <= '9'));
  61.  
  62.     /* If end of input, print answer and return */
  63.     if(c == '\0') {
  64.       *(--out) = '\0';
  65.       puts(outbuff);
  66.       return 0;
  67.     }
  68.  
  69.     /* Read first integer */
  70.     do {
  71.       i = 10 * i + (c - '0');
  72.       c = *(in++);
  73.     } while(c >= '0' && c <= '9');
  74.  
  75.     /* Skip whitespace between first and second integer */
  76.     do {
  77.       c = *(in++);
  78.     } while(!(c >= '0' && c <= '9'));
  79.  
  80.     /* Read second integer */
  81.     do {
  82.       j = 10 * j + (c - '0');
  83.       c = *(in++);
  84.     } while(c >= '0' && c <= '9');
  85.  
  86.     if(i > j)
  87.       res = i-j;
  88.     else
  89.       res = j-i;
  90.  
  91.  
  92.  
  93.     /* Buffer answer */
  94.     if(res == 0) {
  95.       *(out++) = '0';
  96.     } else {
  97.       unsigned long long divisor = divisors[__builtin_clzll(res)-31];
  98.       /* Skip trailing 0 */
  99.       if(res < divisor) {
  100.         divisor /= 10;
  101.       }
  102.       /* Buffer digits */
  103.       while(divisor != 0) {
  104.         unsigned long long digit = res / divisor;
  105.         *(out++) = digit + '0';
  106.         res -= divisor * digit;
  107.         divisor /= 10;
  108.       }
  109.     }
  110.     *(out++) = '\n';
  111.   }
  112. }
Success #stdin #stdout 0s 15064KB
comments (?)
stdin 
10 12
10 14
100 200
stdout 
2
4
100
https://ideone.com/a18qoi
language:
C (gcc 8.3)
created:
8 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!