seqstring* substring(seqstring str, int i, int len) { seqstring* sub = (seqstring*)malloc(sizeof(seqstring)); if (i < 1 || i > str.length || len < 0 || i + len - 1 > str.length) { sub = NULL; return sub; } for (int j = 0; j < len; j++) { sub->data[j] = str.data[i - 1 + j]; } sub->data[len] = '\0'; sub->length = len; return sub; } [2024-10-16 08:51:55 | AI写代码神器 | 146点数解答]