c program to find the class of ip address
#include <stdio.h> #include <string.h> /* Function : extractIpAddress Arguments : 1) sourceString - String pointer that contains ip address 2) ipAddress - Target variable short type array pointer that will store ip address octets */ void extractIpAddress(unsigned char *sourceString,short *ipAddress) { unsigned short len=0; unsigned char oct[4]={0},cnt=0,cnt1=0,i,buf[5]; len=strlen(sourceString); for(i=0;i<len;i++) { if(sourceString[i]!='.'){ buf[cnt++] =sourceString[i]; } if(sourceString[i]=='.' || i==len-1){ buf[cnt]='\0'; cnt=0; oct[cnt1++]=atoi(buf); } } ipAddress[0]=oct[0]; ipAddress[1]=oct[1]; ipAddress[2]=oct[2]; ipAddress[3]=oct[3]; } int main() { unsigned char ip[20]={0}; short ipAddress[4]; printf("Enter IP Address (xxx.xxx.xxx.xxx format): "); scanf("%s",ip); extractIpAddress(ip,&ipAddress[0]); printf("\nIp Address: %03d. %03d. %03d. %03d\n",ipAddress[0],ipAddress[1],ipAddress[2],ipAddress[3]); if(ipAddress[0]>=0 && ipAddress[0]<=127) printf("Class A Ip Address.\n"); if(ipAddress[0]>127 && ipAddress[0]<191) printf("Class B Ip Address.\n"); if(ipAddress[0]>191 && ipAddress[0]<224) printf("Class C Ip Address.\n"); if(ipAddress[0]>224 && ipAddress[0]<=239) printf("Class D Ip Address.\n"); if(ipAddress[0]>239) printf("Class E Ip Address.\n"); return 0; }
