Format Strings

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Format strings specify required formats to general-purpose formatting routines. Format strings passed to the string formatting routines contain two types of objects--literal characters and format specifiers. Literal characters are copied word for word to the resulting string. Format specifiers fetch arguments from the argument list and apply the formatting to them.

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Index, width, and precision specifiers can be specified directly, using a decimal digit string (for example "%10d"). Note that width Width is an integer value, while precision is an unsigned integer value. For example,

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