30 lines
630 B
C
30 lines
630 B
C
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#include <stdlib.h>
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// assumes endptr != NULL
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// doesn't check for sign
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// doesn't check for base-prefix
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long long int strtoll(const char *nptr, char **endptr, int base) {
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long long val = 0;
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for (; *nptr; nptr++) {
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int v = *nptr;
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if ('0' <= v && v <= '9') {
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v -= '0';
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} else if ('A' <= v && v <= 'Z') {
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v -= 'A' - 10;
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} else if ('a' <= v && v <= 'z') {
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v -= 'a' - 10;
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} else {
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break;
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}
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if (v >= base) {
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break;
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}
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val = val * base + v;
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}
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*endptr = (char *)nptr;
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return val;
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}
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