step: add unary operations
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			@ -7,6 +7,15 @@
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#include "mpc/mpc.h"
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#define VERBOSE 1
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long evaluate_unary_operation(char* op, long x)
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{
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    if (!strcmp(op, "+")) {
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        return x;
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    } else if (!strcmp(op, "-")) {
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        return -x;
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		}
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    return 0;
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}
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long evaluate_operation(char* op, long x, long y)
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{
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    if (!strcmp(op, "+")) {
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			@ -17,8 +26,6 @@ long evaluate_operation(char* op, long x, long y)
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        return x * y;
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    } else if (!strcmp(op, "/")) {
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        return x / y;
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    } else if (!strcmp(op, "^")) {
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        return 42; // to take care of later
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    }
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    return 0;
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}
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			@ -31,8 +38,6 @@ int is_ignorable(mpc_ast_t* t){
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long evaluate_ast(mpc_ast_t* t)
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{
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    // Base case #1: It's a number
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    if (VERBOSE)
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        printf("\n\nEvaluating the ast");
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    if (strstr(t->tag, "number")) {
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        if (VERBOSE)
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            printf("\nCase #1, %s", t->contents);
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			@ -46,17 +51,28 @@ long evaluate_ast(mpc_ast_t* t)
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            printf("\nCase #2, %s", t->children[0]->contents);
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        return atoi(t->children[0]->contents);
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    }
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		// Base case #3: Top level parenthesis
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    if (t->children_num == 2 && strstr(t->children[0]->tag, "expr|>") && !strcmp(t->children[1]->tag, "regex")) {
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        if (VERBOSE)
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            printf("\nCase #3, top level parenthesis");
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				return evaluate_ast(t->children[0]);
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    }
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    // Case #4: Unary operations case
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    // Case #5: Binary (or more) operations case
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		// "Real" cases
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    long x;
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    char* operation;
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    // Case #4: Unary operations case
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    if (t->children_num == 3 && is_ignorable(t->children[0]) && strstr(t->children[1]->tag, "operator")) {
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        operation = t->children[1]->contents;
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        if (VERBOSE)
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            printf("\nCase #4, unary operation %s", operation);
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        x = evaluate_ast(t->children[2]);
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        x = evaluate_unary_operation(operation, x);
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    }
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    // Case #5: Binary (or more) operations case
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    if (t->children_num > 3 && is_ignorable(t->children[0]) && strstr(t->children[1]->tag, "operator")) {
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        operation = t->children[1]->contents;
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        if (VERBOSE)
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			@ -80,13 +96,13 @@ void print_ast(mpc_ast_t* ast, int num_tabs)
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		for(int i=0; i<num_tabs;i++){
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			strcat(tabs, "  ");
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		}
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    printf("%sTag: %s\n", tabs, ast->tag);
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    printf("%sContents: %s\n", tabs, strcmp(ast->contents, "") ? ast->contents : "None");
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    printf("%sNumber of children: %i\n", tabs, ast->children_num);
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    printf("\n%sTag: %s", tabs, ast->tag);
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    printf("\n%sContents: %s", tabs, strcmp(ast->contents, "") ? ast->contents : "None");
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    printf("\n%sNumber of children: %i", tabs, ast->children_num);
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    /* Print the children */
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    for (int i = 0; i < ast->children_num; i++) {
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        mpc_ast_t* child_i = ast->children[i];
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        printf("%sChild #%d\n", tabs, i);
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        printf("\n%sChild #%d", tabs, i);
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				print_ast(child_i, 1);
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    }
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}
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			@ -128,7 +144,10 @@ int main(int argc, char** argv)
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                mpc_ast_t* ast = result.output;
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                // Print AST if VERBOSE
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								print_ast(ast, 0);
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								if(VERBOSE) print_ast(ast, 0);
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								// Evaluate the AST
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								if(VERBOSE) printf("\n\nEvaluating the AST");
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                long result = evaluate_ast(ast);
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                printf("\nResult: %li\n", result);
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            } else {
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