C++ Standard Library - phần 2

Tác giả Matt Mahoney, mmahoney@cs.fit.edu.
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C++ cheat sheet – phần 1

C/C++ STANDARD LIBRARY

Only the most commonly used functions are listed. Header files without .h are in namespace std. File names are actually lower case.
STDIO.H, CSTDIO (Input/output)

FILE* f=fopen("filename", "r");  // Open for reading, NULL (0) if error
  // Mode may also be "w" (write) "a" append, "a+" update, "rb" binary
fclose(f);                // Close file f
fprintf(f, "x=%d", 3);    // Print "x=3"  Other conversions:
  "%5d %u %-8ld"            // int width 5, unsigned int, long left just.
  "%o %x %X %lx"            // octal, hex, HEX, long hex
  "%f %5.1f"                // float or double: 123.000000, 123.0
  "%e %g"                   // 1.23e2, use either f or g
  "%c %s"                   // char, char*
  "%%"                      // %
sprintf(s, "x=%d", 3);    // Print to array of char s
printf("x=%d", 3);        // Print to stdout (screen unless redirected)
fprintf(stderr, ...       // Print to standard error (not redirected)
getc(f);                  // Read one char (as an int) or EOF from f
ungetc(c, f);             // Put back one c to f
getchar();                // getc(stdin);
putc(c, f)                // fprintf(f, "%c", c);
putchar(c);               // putc(c, stdout);
fgets(s, n, f);           // Read line into char s[n] from f.  NULL if EOF
gets(s)                   // fgets(s, INT_MAX, f); no bounds check
fread(s, n, 1, f);        // Read n bytes from f to s, return number read
fwrite(s, n, 1, f);       // Write n bytes of s to f, return number written
fflush(f);                // Force buffered writes to f
fseek(f, n, SEEK_SET);    // Position binary file f at n
ftell(f);                 // Position in f, -1L if error
rewind(f);                // fseek(f, 0L, SEEK_SET); clearerr(f);
feof(f);                  // Is f at end of file?
ferror(f);                // Error in f?
perror(s);                // Print char* s and error message
clearerr(f);              // Clear error code for f
remove("filename");       // Delete file, return 0 if OK
rename("old", "new");     // Rename file, return 0 if OK
f = tmpfile();            // Create temporary file in mode "wb+"
tmpnam(s);                // Put a unique file name in char s[L_tmpnam]

STDLIB.H, CSTDLIB (Misc. functions)

atof(s); atol(s); atoi(s);// Convert char* s to float, long, int
rand(), srand(seed);      // Random int 0 to RAND_MAX, reset rand()
void* p = malloc(n);      // Allocate n bytes.  Obsolete: use new
free(p);                  // Free memory.  Obsolete: use delete
exit(n);                  // Kill program, return status n
system(s);                // Execute OS command s (system dependent)
getenv("PATH");           // Environment variable or 0 (system dependent)
abs(n); labs(ln);         // Absolute value as int, long

STRING.H, CSTRING (Character array handling functions)
Strings are type char[] with a ‘