%{ float deger = 0; %} floats ^[+-]?[0-9]*[\.]?[0-9] %% {floats}+[cC]$ { deger = atof(yytext); deger += 273; printf("%.2fK" , deger); } {floats}+[kK]$ { deger = atof(yytext); deger -= 273; printf("%.2fC" , deger); } {floats}+[fF]$ { deger = atof(yytext); deger = (deger-32)/1.8; printf("%.2fC" , deger); } %%