C code. C code run. Run code run… please!
In this article, an stable-cost method is proposed and tested. Previously, the test result showed, the performance of brute force method is the best. Let the number of digits be n. In the best case, in which the integer is … Read More »
Sometimes, we need to know the number of digits in an integer. There are many methods, which could do this work well. Here we list some of them, and compare their performance in different circumstances. Firstly, we post the source … Read More »
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 | // Author: Sheng Yu // Date: 02/09/2013 // // C solution for problem 1.4 in Cracking the Coding Interview 5th eidtion. // // Test environment: gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-52) // #include <stdio.h> #include <string.h> void ReplaceSpaces(char *str, int len){ /* To replace all the spaces in str to "%20" in in-place manner*/ int index = -1; int old_end = len-1; int new_end = old_end; // Compute the end of new string while(++index<len){ if(str[index]==' '){ new_end += 2; } } // Replace the " " to "%20" str[new_end+1] = ' '; while(--index >=0){ if(str[old_end]==' '){ str[new_end--] = '0'; str[new_end--] = '2'; str[new_end--] = '%'; } else{ str[new_end--] = str[old_end]; } --old_end; } return; } int main(){ char test[50] = "Mr John Smith "; printf("Original: %sn",test); ReplaceSpaces(test,strlen(test)); printf("Replaced: %sn",test); return 0; } |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 | // Author: Sheng Yu // Time: 02/05/2013 // // C solution for problem 1.3 in Cracking the Coding Interview 5th eidtion. // // Test environment: gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-52) // #include <stdio.h> #include <string.h> #include <stdbool.h> bool isAnagram(char *str1, char *str2){ // Check whether str1 and str2 are anagram // Works well for ASCII strings with length less than 2^16 // For longer string, overflow might happen int count[256]; int index = -1; if(strlen(str1) != strlen(str2)) return false; memset(count,0,256*sizeof(int)); // Scan str1, get its letters' distribution while(str1[++index] != ' '){ ++count[(unsigned int)str1[index]]; } // Scan str2, and compare its letters' distribution with str1 index = -1; while(str2[++index] != ' '){ --count[(unsigned int)str2[index]]; } index = -1; while( ++ index < 256){ if( count[index] != 0 ) return false; } return true; } int main(int argc, char *argv[]){ if(argc != 3){ printf("Invalid arguments.n"); return 1; } if(isAnagram(argv[1],argv[2])){ printf("They are anagram:nt%snt%sn",argv[1],argv[2]); } else{ printf("They are not anagram.nt%snt%sn",argv[1],argv[2]); } return 0; } |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 | // Author: Sheng Yu // Time: 02/03/2013 // // C solution for problem 1.2 in Cracking the Coding Interview 5th eidtion. // // Test environment: gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-52) // #include <stdio.h> #include <string.h> #define MAXSIZE 256 void reverse(char *str){ char *str_begin = str; char *str_end = str+strlen(str)-1; // Point to the last char char temp; while(str_begin < str_end){ temp = *str_begin; *(str_begin++) = *str_end; *(str_end--) = temp; } return; } int main(int argc, char * argv[]){ if(argc != 2){ printf("Unsuitable arguments!n"); return 1; } char str[MAXSIZE]; str[MAXSIZE-1] = ' '; strncpy(str,argv[1],MAXSIZE-1); printf("ready to work: %sn",str); reverse(str); printf("Work result: %sn",str); return 0; } |
WIith Google search, I find there is a website (http://crack5e.info/) to list the C++ solutions to the problems listed in book Cracking the Coding Interview (5th edition). It is a great website. Thanks to the author! In the following days, … Read More »
System call is a set of special APIs, as the interface between operating system’s kernel and other programs. For example, if a program wants to create a new process, it should actually call a system call to achieve that. In … Read More »
Long long ago, I wrote this piece of code, with Python and pcapy, for my project. Today I put it on my blog, partly for recording, and partly for memento. This program read the data in libpcap file format, filter … Read More »
A hello world program, in most cases, is the first program of newbies. As a newbie of blog, I am happy to begin my site with this hello world article, and a short piece of hello world program in Python3: … Read More »