add prog 14

2 files changed, 109 insertions, 0 deletions

diff --git a/14/main.l b/14/main.l
new file mode 100644
index 0000000..ffcb97e
--- /dev/null
+++ b/14/main.l
@@ -0,0 +1,23 @@
+%{
+#include <stdlib.h>
+extern int yylval;
+%}
+
+%%
+
+[0-9]+? {
+    yylval=yytext[0];
+    return NUM;
+};
+[a-zA-Z]+? {
+    yylval=yytext[0];
+    return IDENT;
+}
+. return yytext[0];
+\n return 0;
+%%
+
+int yywrap() {
+    return 1;
+}
+
diff --git a/14/main.y b/14/main.y
new file mode 100644
index 0000000..8d10b32
--- /dev/null
+++ b/14/main.y
@@ -0,0 +1,86 @@
+%{
+#include<stdio.h>
+#include<string.h>
+#include<stdlib.h>
+#include<ctype.h>
+
+void three_address_code();
+char add_to_table(char ,char, char);
+int yyerror(char *);
+int yylex();
+
+int idx = 0;
+char tvar = '1';
+struct instruction {
+    char op1;
+    char op2;
+    char opr;
+};
+%}
+
+%token IDENT NUM
+%type expr
+%left '+'
+%left '*''/'
+%left '-'
+%%
+
+statement: IDENT '=' expr ';' { add_to_table((char)$1, (char)$3, '='); }
+         | expr ';'
+         ;
+
+expr: expr '+' expr {$$ = add_to_table((char)$1, (char)$3, '+');}
+    | expr '-' expr {$$ = add_to_table((char)$1, (char)$3, '-');}
+    | expr '*' expr {$$ = add_to_table((char)$1, (char)$3, '*');}
+    | expr '/' expr {$$ = add_to_table((char)$1, (char)$3, '/');}
+    | '(' expr ')' {$$ = (char)$2;}
+    | NUM {$$ = (char)$1;}
+    | IDENT {$$ = (char)$1;}
+    | '-' expr {$$ = add_to_table((char)$2, (char)'\t', '-');}
+    ;
+
+%%
+
+int yyerror(char *s) {
+    printf("ERROR: %s",s);
+    exit(0);
+}
+
+struct instruction ops[20];
+
+char add_to_table(char op1, char op2, char opr) {
+    ops[idx].op1 = op1;
+    ops[idx].op2 = op2;
+    ops[idx].opr = opr;
+    idx++;
+    return tvar++;
+}
+
+void three_address_code() {
+    int count = 0;
+    char temp = '1';
+    while(count < idx) {
+        if(ops[count].opr != '=') {
+            printf("t%c=", temp++);
+        }
+        if(isalpha(ops[count].op1)) {
+            printf("%c",ops[count].op1);
+        } else if(ops[count].op1 >='1' && ops[count].op1 <='9') {
+            printf("t%c",ops[count].op1);
+        }
+
+        printf("%c",ops[count].opr);
+
+        if(isalpha(ops[count].op2)) {
+            printf(" %c\n",ops[count].op2);
+        } else if(ops[count].op2 >='1' && ops[count].op2 <='9') {
+            printf("t%c\n",ops[count].op2);
+        }
+        count++;
+    }
+}
+
+int main() {
+    yyparse();
+    three_address_code();
+}