#include <stdio.h>
int main(void)
{
unsigned int x;
unsigned char ch = 'Y';
unsigned char test_num = 0; //count the test numbers
puts("Please input the number (between 0 and 65535, which of them are included) you want to test:");
while('Y' == ch)
{
if(test_num)
printf("again now...\n"
"enter the number:\n");
scanf("%ud",&x);
getchar();
unsigned int temp = x;
int ret = 0;
for(; temp; temp&=(temp-1))
{
ret++;
}
printf("There %s %d '1'%s in the num %d\n",(ret>1)?"are":"is",ret,(ret>1)?"s":"",x);
test_num++;
printf("No %d tested number.\n",test_num);
printf("-----------------------------------\n");
puts("want ot again? Y to continue, N to finish:");
scanf("%c",&ch);
}
puts("Bye...");
return 0;
}测试结果：
G:\desktop\huiwenTest>bits.exe
Please input the number (between 0 and 65535, which of them are included) you want to test:
256
There is 1 '1' in the num 256
No 1 tested number.
-----------------------------------
want ot again? Y to continue, N to finish:
Y
again now...
enter the number:
369
There are 5 '1's in the num 369
No 2 tested number.
-----------------------------------
want ot again? Y to continue, N to finish:
Y
again now...
enter the number:
512
There is 1 '1' in the num 512
No 3 tested number.
-----------------------------------
want ot again? Y to continue, N to finish:
Y
again now...
enter the number:
511
There are 9 '1's in the num 511
No 4 tested number.
-----------------------------------
want ot again? Y to continue, N to finish:
Y
again now...
enter the number:
65535
There are 16 '1's in the num 65535
No 5 tested number.
-----------------------------------
want ot again? Y to continue, N to finish:
N
Bye...