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Test
// description of your code here
//1:递归的就3行解决问题,ä¸?过呢比较挫的机å?上溢出,整个é?žé€’å½’çš„
unsigned int Fibonacci(unsigned int a)
{
unsigned int tmp[2]={0,1};
bool flag = true;
if(a == 0) return 0;
if(a == 1) return 1;
for(int i = 0; i < a-1; i++)
{
tmp[!flag] += tmp[flag];
flag = !flag;
}
return tmp[flag];
}
void problem1(char* filename)
{
ifstream infile(filename);
assert(filename);
int val;
while(infile>>val)
{cout<<Fibonacci(val)<<endl;}
infile.close();
}
//2:就一体力活。。。
const static char keys[][13]=
{
{'`', '1', '2', '3', '4', '5' ,'6', '7' ,'8' ,'9', '0', '-' ,'='},
{'Q', 'W', 'E', 'R', 'T' ,'Y', 'U', 'I', 'O', 'P' ,'[', ']', '\\'},
{'A' ,'S' ,'D' ,'F' ,'G' ,'H' ,'J', 'K' ,'L' ,';', '\''},
{'Z', 'X' , 'C', 'V' , 'B' , 'N', 'M', ',' , '.', '/'}
};
static unsigned char charmap[256];
void buildmap()
{
int i, j;
for(i = 0; i < 256; i++)charmap[i] = i;
for(j =0; j < 4; j++)
for(i = 1; i < 13; i++)
{
if(keys[j][i])
{
charmap[keys[j][i]] = keys[j][i-1];
if(keys[j][i] >= 'A' && keys[j][i] <= 'Z')
charmap[keys[j][i]+32] = keys[j][i]+32;
}
}
}
void problem2(const char* filename)
{
static bool isinitmap = false;
int chr;
FILE *fp = fopen(filename, "r");
assert(filename);
if(!isinitmap){ buildmap(); isinitmap = true;}
while((chr = fgetc(fp)) != EOF)
{
printf("%c", (char)charmap[chr]);
}
fclose(fp);
}
#if 0
3:如果对STL的string有那么一点点了解的�会比较简�,如果想裸写KMP,
还是比较困难,�过暴力的O(m*n)的倒是简�,估计也能accept :-)
#endif
typedef basic_string<char>::size_type str_pos;
int string_shift(string& T, string P)
{
str_pos start = -1;
int shift_cnt = 0;
while((start = T.find(P, start+1)) != -1)shift_cnt++;
return shift_cnt;
}
void strshift(char* filename)
{
ifstream infile(filename);
assert(infile);
string T, P;
while(infile>>T>>P)cout << string_shift(T, P)<<endl;
infile.close();
}
//4:一个简�的办法就是递归啦,�过注�2的表示是2 �是2(2(0))就好了。
#define BITMASK (0x1<<31)
void exponentform(unsigned int a)
{
if(a == 0 || a == 2)
{
cout << a;
return;
}
for(int i = 31; i > -1; i--)
{
if(a & BITMASK)
{
if(i == 1)
{
cout << "2";
}
else
{
cout<<"2(";
exponentform(i);
cout << ")";
}
if(a<<1)cout << "+";
//
}
a <<= 1;
}
}
void problem4(char* filename)
{
ifstream infile(filename);
int val;
while(infile>>val)
{
exponentform(val);
puts("");
}
infile.close();
}




