kdeng00
83 lines
1.4 KiB
C
83 lines
1.4 KiB
C
/*
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*
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* Exercise 2-10. Rewrite the function lower, which converts upper case
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* letters to lower case, with a conditional expression instead of
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* if-else.
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*
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* Author: Kun Deng
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <ctype.h>
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char lowered[50];
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// Makes the string lower case
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char *lower(char *value);
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// Returns 1 if value is a valid alphabetic value and 0 if invalid
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int is_valid(char *value);
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int main(int argc, char **argv)
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{
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char *x = "soSSDFrSDGFtSGngSGDeSGD\0";
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if (argc == 2)
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{
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x = argv[1];
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}
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int result = is_valid(x);
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if (result == 1)
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{
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printf("%s is a valid alphabetic value\n", x);
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char *lowered = lower(x);
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printf("%50s %10s %50s\n", "Regular", "|", "Lowered");
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printf("%50s %10s %50s\n", x, "|", lowered);
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}
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else if (result == 0)
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{
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printf("%s is not a valid alphabetic value\n", x);
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}
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return 0;
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}
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char *lower(char *value)
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{
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extern char lowered[];
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int result = 0;
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int a;
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for (a = 0; value[a] != '\0'; ++a)
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{
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char c = value[a];
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// printf("%c ", c);
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lowered[a] = (isupper(c) ? tolower(c) : c);
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}
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lowered[a] = '\0';
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return lowered;
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}
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int is_valid(char *value)
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{
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int result = 1;
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for (int i = 0; value[i] != '\0'; ++i)
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{
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if (!isalpha(value[i]))
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{
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result = 0;
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break;
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}
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}
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return result;
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}
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