int biTofh(int bi,int len){//二进制转化为正负号         int i=0;         while(i<len){                 int tmp = 1;                 if((bi & (tmp<<(len-i-1))) != 0){//从最左位开始比较，该位是1                         printf(" + ");                 }                 else{                         printf(" - ");                 }                 i++;            }         printf("\n");         return 0; } int main(){         int input[] = {1,2,3,4,5};         biTofh(20,5);         return 0; }

xu@xu-ThinkPad-X61:~/algorithm$ ./a.out  +  -  +  -  - xu@xu-ThinkPad-X61:~/algorithm$