C program to add two polynomials using structures

Write a C program to add two polynomials using structures.

  #include <stdio.h>
  #include <stdlib.h>

  struct polynomial {
        int power;
        float coeff;
  };

  int main() {
        struct polynomial *p1, *p2, *p3;
        int i, pow1, pow2, max, flag = 0;

        /* get the max powers of first and second polynomial */
        printf("Maximum power in first polynomial:");
        scanf("%d", &pow1);

        printf("Maximum power in second polynomial:");
        scanf("%d", &pow2);

        /* dynamic memory allocation for input polynomials */
        p1 = (struct polynomial *)calloc(sizeof(struct polynomial), pow1 + 1);
        p2 = (struct polynomial *)calloc(sizeof(struct polynomial), pow2 + 1);

        /* get the first polynomial input from the user */
        printf("Enter your input for first polynomial:\n");
        for (i = 0; i <= pow1; i++) {
                printf("%dX^%d => ", i , i);
                (p1 + i)->power = i;
                printf("Coefficient:");
                scanf("%f", &((p1 + i)->coeff));
        }

        /* get the second polynomial input from the user */

        printf("Enter your input for second polynomial:\n");

        for (i = 0; i <= pow2; i++) {

                printf("%dX^%d => ", i , i);

                (p2 + i)->power = i;

                printf("Coefficient:");

                scanf("%f", &((p2 + i)->coeff));

        }

        max = pow1 > pow2 ? pow1 : pow2;

        /* dynamically allocate memory for output polynomial */

        p3 = (struct polynomial *)calloc(sizeof(struct polynomial), max + 1);

        /* add given two polynomials and store the result in output polynomial */

        for (i = 0; i <= max; i++) {

                if (i <= pow1 && i <= pow2) {

                        (p3 + i)->power = (p1 + i)->power;

                        (p3 + i)->coeff = (p1 + i)->coeff + (p2 + i)->coeff;

                } else if (i <= pow1) {

                        (p3 + i)->power = (p1 + i)->power;

                        (p3 + i)->coeff = (p1 + i)->coeff;

                } else {

                        (p3 + i)->power = (p2 + i)->power;

                        (p3 + i)->coeff = (p2 + i)->coeff;

                }

        }

        /* print the results */

        printf("Sum of the given two polynomials:\n");

        for (i = max; i >= 0; i--) {

                if (flag)

                        printf(" + ");

                printf("%.1fX^%d", (p3 + i)->coeff, (p3 + i)->power);

                flag = 1;

        }

        printf("\n");

        return 0;

  }

  Output:

  jp@jp-VirtualBox:~/$ ./a.out
  Maximum power in first polynomial:5
  Maximum power in second polynomial:3
  Enter your input for first polynomial:
  0X^0 => Coefficient:1
  1X^1 => Coefficient:2
  2X^2 => Coefficient:3
  3X^3 => Coefficient:4
  4X^4 => Coefficient:5
  5X^5 => Coefficient:6
  Enter your input for second polynomial:
  0X^0 => Coefficient:1
  1X^1 => Coefficient:2
  2X^2 => Coefficient:3
  3X^3 => Coefficient:4

  Sum of the given two polynomials:
  6.0X^5 + 5.0X^4 + 8.0X^3 + 6.0X^2 + 4.0X^1 + 2.0X^0