8)RECURSIVE DESCENT PARSER

#include <stdio.h>
#define SUCCESS 1
#define FAILED 0

const char *cursor;
char input[64];

int E(), Edash(), T(), Tdash(), F();

int main() {
    printf("Enter the string: ");
    scanf("%s", input);
    cursor = input;

    printf("\nInput         Action\n");
    printf("-------------------------------\n");

    if (E() && *cursor == '\0') {
        printf("-------------------------------\n");
        printf("String is successfully parsed\n");
    } else {
        printf("-------------------------------\n");
        printf("Error in parsing String\n");
    }
    return 0;
}

int E() {
    printf("%-15s E -> T E'\n", cursor);
    return T() && Edash();
}

int Edash() {
    if (*cursor == '+') {
        printf("%-15s E' -> + T E'\n", cursor);
        cursor++;
        return T() && Edash();
    }
    printf("%-15s E' -> ε\n", cursor);
    return SUCCESS;
}

int T() {
    printf("%-15s T -> F T'\n", cursor);
    return F() && Tdash();
}

int Tdash() {
    if (cursor == '') {
        printf("%-15s T' -> * F T'\n", cursor);
        cursor++;
        return F() && Tdash();
    }
    printf("%-15s T' -> ε\n", cursor);
    return SUCCESS;
}

int F() {
    if (*cursor == '(') {
        printf("%-15s F -> ( E )\n", cursor);
        cursor++;
        if (E() && *cursor == ')') {
            cursor++;
            return SUCCESS;
        }
        return FAILED;
    } else if (*cursor == 'i') {
        printf("%-15s F -> i\n", cursor);
        cursor++;
        return SUCCESS;
    }
    return FAILED;
}