ParseTree.c

#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <stdbool.h>
#include <stdlib.h>
int isUpper(char c)
{
    if (c >= 'A' && c <= 'Z')
        return 1;
    else
        return 0;
}
char *subString(char *str, int left, int right)
{
    int i;
    char *subStr = (char *)malloc(
        sizeof(char) * (right - left + 2));
    for (i = left; i <= right; i++)
        subStr[i - left] = str[i];
    subStr[right - left + 1] = '\0';
    return (subStr);
}
int main()
{
    char production[10][10], s[200];
    char *refStr;
    int cnt = 5, f = -1;
    strcpy(production[0], "S-T+S");
    strcpy(production[1], "T-c*T");
    strcpy(production[2], "S-T");
    strcpy(production[3], "T-c");
    strcpy(production[4], "T-(S)");
    printf("\nOriginal Grammar: \n");
    for (int i = 0; i < cnt; i++)
    {
        printf("%s", production[i]);
        printf("\n");
    }
    printf("\nEnter Language : ");
    scanf("%[^\n]%*c", s);
    refStr = subString(s, 2, strlen(s));
    printf("\n\nUpdates in main Production Grammar : \n");
    printf("%s", production[0]);
    for (int i = 1; i < cnt; i++)
    {
        char *shortStr = subString(production[0], 2,
                                   strlen(production[0]));
        char modStr[30] = "";
        strcat(modStr, "S-");
        for (int k = 0; k < strlen(shortStr); k++)
        {
            if (shortStr[k] == production[i][0])
            {
                char *useStr = subString(production[i],
                                         2, strlen(production[i]));
                strcat(modStr, useStr);
            }
            else
            {
                strncat(modStr, &shortStr[k], 1);
            }
        }
        printf("\n%s", modStr);
        strcpy(production[0], modStr);
        char *finStr = subString(modStr, 2,
                                 strlen(modStr));
        int terminate = 0;
        for (int r = 0; r < strlen(finStr); r++)
        {
            if (isUpper(finStr[r]))
            {
                terminate = 1;
                break;
            }
        }
        if (!strcmp(finStr, refStr) && terminate != 1)
        {
            f = 1;
            break;
        }
    }
    if (f == 1)
    {
        printf("\n\n%s Language can be derived from the Original grammar.\n\n", s);
    }
    else
    {
        printf("\n\n%s Language cannot be derived from the Original grammar.\n\n", s);
    }
    return 0;
}