Coding Club Of Competitive Programmers

 Implementation of Calculator using LEX and YACC Lex<Cal.L> %{ #include"y.tab.h" #include<math.h> %} %% ([0-9]+|([0-9]*\.[0-9]+)([eE][-+]?[0-9]+)?) {yylval.dval=atof(yytext);return NUMBER;} log | LOG {return LOG;} In {return nLOG;} sin | SIN {return SINE;} cos | COS {return COS;} tan | TAN {return TAN;} mem {return MEM;} [\t]; \$ return 0; \n|. return yytext[0]; %% Yacc<Cal.Y> %{ double memvar; %} %union { double dval; } %token<dval>NUMBER %token<dval>MEM %token LOG SINE nLOG COS TAN %left '-' '+' %left '*' '/' %right '^' %left LOG SINE nLOG COS TAN %nonassoc UMINUS %type<dval>expression %% start:statement'\n' |start statement'\n' ; statement:MEM'='expression {memvar=$3;} | expression{printf("Answer=%g\n",$1);} ; expression:expression'+'expression {$$=$1+$3;} | expression '-' expression {$$=$1-$3;} | expression '*' expression {$$=$1*$3;} | expr...