小编kap*_*pil的帖子

我们(人)花费更多的时间来乘法,加法,除法和减去两个大数而不是两个小数.

计算机是否需要花费更多时间来5 * 2表示51234 * 987654或者是否在相同的时间内完成操作？

两个大于处理器字长的数字(例如两个128位数)怎么办？

我看到了文章https://en.wikipedia.org/wiki/Multiplication_algorithm

我写了一个程序

include<stdio.h>
struct record
{
    int i;
    char ch[20];
};
int main()
{
    struct record a,*b;
    b=&a;
    printf("intial pointer is %p and final is %p",b++,b);
    return 0;
}

a的大小应为20 + 4 = 24,但输出为

intial pointer is 0x7fffb0455e40 and final is 0x7fffb0455e58

算术是18个字节.为什么输出是这样的？

我写了这个程序

#include<stdio.h>
struct student
{
    char name[22];
    char rollno[10];
    unsigned long long int phno;

};
int main()
{
    int i,j;
    char c[1];
    struct student cse[10],*p;
    p=cse;
    for(i=0;i<3;i++)
    {
            printf("enter student name\n");
            gets(cse[i].name);
            printf("enter student roll number \n");
            gets(cse[i].rollno);
            printf("enter student phone number \n");
            scanf("%llu",&cse[i].phno);
            gets(c); //to catch the '\n' left unprocessed by scanf
    }
    for(i=0;i<3;i++);
    printf("the following is the information about CSE B student\n");
    printf("%-6s%-24s%-14s%-14s \n","S.no","student Name","Roll no","phone no.");
    for(i=0;i<3;i++)
    {
            printf("%-6d%-24s%-20s%-14llu \n",i+1,(*p).name,(*p).rollno,(*p).phno);
            ++p;
    }
    return 0;
}

输出是

the …

我写了一个程序

#include<stdio.h>
int main()
{
      int x=3;
       if((x)==1,2,4,5,6)
               printf("number found in the list\n");
       else
               printf("Number not found \n");

      return 0;
}

我期待输出为"未找到数字",但它是"在列表中找到的数字"为什么会这样

#include<stdio.h>
static int main()
{
   printf("foo");
   return 0;
}

代码给出了错误

nfo): relocation 12 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 13 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 14 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 15 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 16 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 17 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 18 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 19 has invalid symbol index …