// 989. Add to Array-Form of Integer #include #include #include /* * the array-form of an integer 'num' is an array representing its digits in * left to right order. eg 'num = 1231', the array form is 1,3,2,1. given 'num', * the array form of an integer, and an integer 'k', return the array-form of * 'num + k' */ int *addToArrayForm(int *num, int numSize, int k, int *returnSize) { int *k_arr, *ans, k_size, r_size, p; for (int i = k, k_size = 0; i > 0; i /= 10) k_size++; k_arr = malloc(sizeof(int) * k_size); for (int i = k_size - 1, p = k; i >= 0; p /= 10) k_arr[i--] = p % 10; r_size = k_size > numSize ? k_size : numSize; ans = malloc(sizeof(int) * (++r_size)); for (int i = numSize, j = k_size, c = 0, p = r_size - 1; p >= 0; p--) { c += i > 0 ? num[--i] : 0; c += j > 0 ? k_arr[--j] : 0; ans[p] = c % 10; c /= 10; } if (ans[0] == 0) memmove(ans, ans + 1, sizeof(int) * (--r_size)); *returnSize = r_size; free(k_arr); return ans; } int main() { int num1[] = {1, 2, 0, 0}, ns1 = 4, k1 = 34, rs1[] = {4}; int num2[] = {2, 7, 4}, ns2 = 3, k2 = 181, rs2[] = {3}; int num3[] = {2, 1, 4}, ns3 = 3, k3 = 806, rs3[] = {4}; printf("%d\n" * addToArrayForm(num1, ns1, k1, rs1)); printf("%d\n" * addToArrayForm(num2, ns2, k2, rs2)); printf("%d\n" * addToArrayForm(num3, ns3, k3, rs3)); }