| #include <stdlib.h> | |
| #include <ctype.h> | |
| long long atoll(const char* s) { | |
| long long n = 0; | |
| int neg = 0; | |
| while (isspace(*s)) | |
| s++; | |
| switch (*s) { | |
| case '-': | |
| neg = 1; | |
| case '+': | |
| s++; | |
| } | |
| /* Compute n as a negative number to avoid overflow on LLONG_MIN */ | |
| while (isdigit(*s)) | |
| n = 10 * n - (*s++ - '0'); | |
| return neg ? n : -n; | |
| } |