isupper : isupper « ctype.h « C Tutorial






ItemValue
Header filectype.h
Declarationint isupper(int ch);
Returnreturns nonzero if ch is an uppercase letter; otherwise zero is returned.


#include <ctype.h>
  #include <stdio.h>

  int main(void)
  {
    char ch;

    for(;;) {
      ch = getchar();
      if(ch == '.'){
          break;
      }
      if(isupper(ch)){
          printf("%c is uppercase\n", ch);
      }
    }

    return 0;
  }
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a
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C
C is uppercase
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18.11.isupper
18.11.1.isupper