%{
#include <stdio.h>
#include <stdlib.h>
 
int num1 = -1, num2 = -1;
%}
 
%%
 
[0-9]+  {
            if (num1 == -1) {
                num1 = atoi(yytext);
            } else {
                num2 = atoi(yytext);
            }
        }
 
"+"     {
            ; // This simply matches the plus sign, no action needed
        }
 
\n      {
            if (num1 != -1 && num2 != -1) {
                printf("Sum: %d\n", num1 + num2);
                num1 = -1;
                num2 = -1;
            } else {
                printf("Error: Two numbers required for addition.\n");
            }
        }
 
.       { ; }
 
%%
 
int main() {
    yylex();
    return 0;
}
 

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