数组运算-搜索

#include 

int amount[] = {1,5,10,25,50};
char *name[] = {"penny","nickel","dime","quarter","half-dollar"};

int search(int key,int a[],int len)
{
	int ret = -1;
	int i;
	for( i=0; i-1 )
	{
		printf("%sn",name[r]);
	}
    return 0;
}

上述代码(因为两种割裂的数组)对计算机cache不友好；

#include 

int amount[] = {1,5,10,25,50};
char *name[] = {"penny","nickel","dime","quarter","half-dollar"};

struct {
	int amount;
	char *name;
} coins[] = {
    {1,"penny"},
    {5,"nickel"},
    {10,"dime"},
    {25,"quarter"},
    {50,"half-dollar"},
};

int main()
{
	int k = 25;
	int i;
	for (i=0; i 
 
 
使用gcc编译代码是报出
 
 
error: 'for' loop initial declarations are only allowed in C99 mode
 
 
note: use option -std=c99 or -std=gnu99 to compile your code
 
 
这是因为在gcc中直接在for循环中初始化了增量：
     for(int i=0; i 这语法在gcc中是错误的，必须先先定义i变量：
 int i;
 for(i=0;i 
这是因为gcc基于c89标准，换成C99标准就可以在for循环内定义i变量了：
 
gcc src.c -std=c99 -o src