なお、fastと使うときは、テストケースにインパクトが有ることに注意しましょう、とのこと。 (実際にはplatformによって、幅が違うから。) intにすべきか、そうでないか The ISO/IEC 9899:1990 standard specified that the language should support four signed and unsigned integer data types- char, short, int, and long- but placed very little requirement on their size other than that int and short be at least 16 bits and long be at least as long as int and not smaller than 32 bits.
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