里面包含很多c语言的源码

				/* Demonstration of printf(). */
				
				#include 
				
				char *m1 = "Binary";
				char *m2 = "Decimal";
				char *m3 = "Octal";
				char *m4 = "Hexadecimal";
				
				int main( void )
				{
				    float d1 = 10000.123;
				    int n, f;
				
				
				    puts("Outputting a number with different field widths.\n");
				
				    printf("%5f\n", d1);
				    printf("%10f\n", d1);
				    printf("%15f\n", d1);
				    printf("%20f\n", d1);
				    printf("%25f\n", d1);
				
				    puts("\n Press Enter to continue...");
				    fflush(stdin);
				    getchar();
				
				    puts("\nUse the * field width specifier to obtain field width");
				    puts("from a variable in the argument list.\n");
				
				    for (n=5;n				        printf("%*f\n", n, d1);
				
				    puts("\n Press Enter to continue...");
				    fflush(stdin);
				    getchar();
				
				    puts("\nInclude leading zeros.\n");
				
				    printf("%05f\n", d1);
				    printf("%010f\n", d1);
				    printf("%015f\n", d1);
				    printf("%020f\n", d1);
				    printf("%025f\n", d1);
				
				    puts("\n Press Enter to continue...");
				    fflush(stdin);
				    getchar();
				
				    puts("\nDisplay in octal, decimal, and hexadecimal.");
				    puts("Use # to precede octal and hex output with 0 and 0X.");
				    puts("Use - to left-justify each value in its field.");
				    puts("First display column labels.\n");
				
				    printf("%-15s%-15s%-15s", m2, m3, m4);
				
				    for (n = 1;n< 20; n++)
				        printf("\n%-15d%-#15o%-#15X", n, n, n);
				
				    puts("\n Press Enter to continue...");
				    fflush(stdin);
				    getchar();
				
				    puts("\n\nUse the %n conversion command to count characters.\n");
				
				    printf("%s%s%s%s%n", m1, m2, m3, m4, &n);
				
				    printf("\n\nThe last printf() output %d characters.\n", n);
				
				    return 0;
				}