#include #include using namespace std; /* Variable validation in C++ by akib @feb 3, 2019 Enter a variable name, the program checks whether its a valid variable in C/C++ */ void log(const char *msg=""){ cout << msg <> var; //checks for numbers at the start of the name char nums[] = "0123456789"; for(int i = 0; i < 10; i++){ if(var[0] == nums[i] ){ log("Invalid variable name:"); log("Variable name starts with a number"); return 0; } } //check for the special characters const char inval_char[] = "^~/@#%&*-+!?"; int len = sizeof(inval_char); for(int j = 0; j < strlen(var); j++){ for(int k = 0; k < len; k++){ if(var[j] == inval_char[k]){ log("Invalid variable name."); log("Variable name cannot contain: "); log(inval_char); return 0; } } } for(int i = 0; i < sizeof(key_words)/10; i++){ //checks for keywords of language if(key_words[i][0] == var[0]){ if(strcmp(key_words[i], var) == 0){ log("Invalid variable name: Name matches name of a keyword"); return 0; } } } log("Valid variable name."); return 0; }

Valid Variable