59 lines
970 B
C
59 lines
970 B
C
#include <stdlib.h>
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#include <string.h>
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#include <stdio.h>
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char shift(char c, int by)
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{
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int start = 0;
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if(c >= 'a' && c <= 'z')
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{
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start = 'a';
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}
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else if(c >= 'A' && c <= 'Z')
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{
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start = 'A';
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}
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else return c;
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c -= start;
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c += by;
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c %= 26;
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return c + start;
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}
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char *reverse_shifted(char *input, int by)
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{
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if(!input)
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{
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return NULL;
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}
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int len = strlen(input);
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char *res = calloc(len, sizeof(char));
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if(!res)
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{
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return NULL;
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}
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int start = 0;
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int end = len + 1;
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for (int i = 0; i < len; i++)
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{
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char val = input[end--];
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val = shift(val, by);
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res[start++] = val;
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}
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return res;
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}
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int main(void)
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{
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char *test1 = "!qxsbdc k cs csrd";
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char *res1 = reverse_shifted(test1, 42);
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if(!res1)
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{
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return EXIT_FAILURE;
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}
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printf("%s",res1);
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puts(res1);
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free(res1);
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return EXIT_SUCCESS;
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}
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