#pragmaGCCoptimize(3)#pragmaGCCtarget("avx")#pragmaGCCoptimize("Ofast")#pragmaGCCoptimize("inline")#pragmaGCCoptimize("-fgcse")#pragmaGCCoptimize("-fgcse-lm")#pragmaGCCoptimize("-f

[题目通道](Welcomehome,Chtholly-洛谷)#include<iostream>#pragmaGCCoptimize(1)#pragmaGCCoptimize(2)#pragmaGCCoptimize(3)#pragmaGCCtarget("avx")#pragmaGCCoptimize("Ofast")#pragmaGCCoptimize("inline")#pra

#pragmaGCCoptimize(3)#pragmaGCCtarget("avx,sse2,sse3,sse4,mmx")#pragmaGCCoptimize("Ofast")#pragmaGCCoptimize("inline")#pragmaGCCoptimize("-fgcse")#pragmaGCCoptimize("-fgcse-lm")#pragmaGC

点击查看代码%:pragmaGCCoptimize(3)%:pragmaGCCoptimize("Ofast")%:pragmaGCCoptimize("inline")%:pragmaGCCoptimize("-fgcse")%:pragmaGCCoptimize("-fgcse-lm")%:pragmaGCCoptimize("-fipa-sra")%:pragma

1.调换搜索顺序2.调换枚举顺序3.快读快输4.位运算5.循环展开6.register7.longlong只在必要开8.函数里在if里return9.火车头%:pragmaGCCoptimize(3)%:pragmaGCCoptimize("Ofast")%:pragmaGCCoptimize("inline")%:pragmaGCCoptimize("-fgcse")%:pragmaGCC

一般来说，如果不指定优化标识的话，gcc就会产生可调试代码，每条指令之间将是独立的：可以在指令之间设置断点，使用gdb中的p命令查看变量的值，改变变量的值等。并且把获取最快的编译速度作为它的目标。    当优化标识被启用之后，gcc编译器将会试图改变程序的结构（当然会在保证变换之后

加在代码最前面可以优化运行速度，亲测有效！#pragmaGCCoptimize(3)#pragmaGCCtarget("avx")#pragmaGCCoptimize("Ofast")#pragmaGCCoptimize("inline")#pragmaG

赛场小寄巧Part1卡常出奇迹把这个玩意加在代码前面会有奇效~#pragmaGCCoptimize(3)#pragmaGCCtarget("avx")#pragmaGCCoptimize("Ofast")#pragmaGCCoptimi

试了一下，去掉火车头本地测试跑了9.1s...加上后是1.0s，神奇地AC了还有就是好像关了流同步的cin和cout甚至比快读orscanf来得快 #pragmaGCCoptimize(3)#pragmaGCC