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printf Precision: Integer Types
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─────Run-Time Library───────────────────────────────────────────────────────
 
     Integer types are d, i, u, o, x, and X.
 
     See: printf Type Characters
 
     With these types, the precision value specifies the minimum number
     of digits printed. If the number of digits in the argument is less
     than the precision value, the output value is padded on the left
     with zeros. The value is not truncated if the number of digits
     exceeds the precision value.
 
     The precision value defaults to 1, but if a period (.) appears
     with no number following it, the precision is set to 0.
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