问题描述 离散傅立叶变换在信号处理中扮演者重要的角色.利用傅立叶变换,可以实现信号在时域和频域之间的转换. 对于一个给定的长度为n=2m (m为整数) 的复数序列X0, X1, …, Xn-1,离散傅立叶变换将得到另一个长度为n的复数序列Y0, Y1, …, Yn-1.其中 Yi=X0+X1wi+ X2w2i+ X3w3i+…+ Xn-1w(n-1)i 其中w=e2πI/n=cos(2π/n)+I sin(2π/n),称为旋转因子,其中I为虚数单位,I2= –1. 给定输入序列X,请输出傅立叶变…

On a broken keyboard, some of the keys are worn out. So when you type some sentences, the characters corresponding to those keys will not appear on screen. Now given a string that you are supposed to type, and the string that you actually type out, p…

输入:只能输入A-Z(不区分大小写),0-9和下划线: 第一行输入应输入字符串,第二行输入实际输入字符串. 输出:按大写输出缺少的字符,每个字符输出一次. 注意: 1.由于不区分大小写,则需要将小写字母识别为大写字母: 2.保证每个字符只出现一次. 思路: 1.将所有的字母都转化为大写字母: 2.挨个枚举第一个字符串,如果在第二个字符串中没有出现,且HashTable数组为false,则输出,HashTable值改为true. #include<cstdio> #include<cstr…

On a broken keyboard, some of the keys are worn out. So when you type some sentences, the characters corresponding to those keys will not appear on screen. Now given a string that you are supposed to type, and the string that you actually type out, p…

1084 Broken Keyboard (20 分) On a broken keyboard, some of the keys are worn out. So when you type some sentences, the characters corresponding to those keys will not appear on screen. Now given a string that you are supposed to type, and the string t…

Source: PAT A1084 Broken Keyboard (20 分) Description: On a broken keyboard, some of the keys are worn out. So when you type some sentences, the characters corresponding to those keys will not appear on screen. Now given a string that you are supposed…

专题一  字符串处理 A1001 Format(20) #include<cstdio> int main () { ]; int a,b,sum; scanf ("%d %d",&a,&b); sum=a+b; ) { printf ("-"); sum=-sum; } ; ) { s[top++]=; } ) { s[top++]=sum%; sum/=; } ;i>=;i--) { printf ("%d"…