icg1.c

#include <stdio.h>
#include <string.h>

int i = 1, j = 0, no = 0, tmpch = 90;
char str[100], left[15], right[15];

struct exp {
    int pos;
    char op;
} k[15];

void findopr();
void explore();
void fleft(int);
void fright(int);

int main() {
    printf("\t\tINTERMEDIATE CODE GENERATION\n\n");
    printf("Enter the Expression :");
    scanf("%s", str);
    printf("The intermediate code:\t\tExpression\n");
    findopr();
    explore();
    return 0;
}

void findopr() {
    char operators[] = "=/*+-";
    for (i = 0; str[i] != '\0'; i++) {
        for (int opIndex = 0; operators[opIndex] != '\0'; opIndex++) {
            if (str[i] == operators[opIndex]) {
                k[j].pos = i;
                k[j++].op = operators[opIndex];
            }
        }
    }
}

void explore() {
    i = 1;
    while (k[i].op != '\0') {
        fleft(k[i].pos);
        fright(k[i].pos);
        str[k[i].pos] = tmpch--;
        printf("\t%c := %s%c%s\t\t", str[k[i].pos], left, k[i].op, right);
        for (j = 0; j < strlen(str); j++) {
            if (str[j] != '$') {
                printf("%c", str[j]);
            }
        }
        printf("\n");
        i++;
    }
    fright(-1);
    if (no == 0) {
        fleft(strlen(str));
        printf("\t%s := %s", right, left);
    } else {
        printf("\t%s :=  %c", right, str[k[--i].pos]);
    }
}

void fleft(int x) {
    int w = 0, flag = 0;
    x--;
    while (x != -1 && strchr("=/*+-", str[x]) == NULL) {
        if (str[x] != '$' && flag == 0) {
            left[w++] = str[x];
            left[w] = '\0';
            str[x] = '$';
            flag = 1;
        }
        x--;
    }
}

void fright(int x) {
    int w = 0, flag = 0;
    x++;
    while (x != -1 && strchr("=/*+-", str[x]) == NULL) {
        if (str[x] != '$' && flag == 0) {
            right[w++] = str[x];
            right[w] = '\0';
            str[x] = '$';
            flag = 1;
        }
        x++;
    }
}