Assigning memory to double pointer?

Question

I am having trouble understanding how to assign memory to a double pointer. I want to read an array of strings and store it.

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Answer 1

i will give one example, which might clear of the doubt,

char **str;                              // here its kind a equivalent to char *argv[]
str = (char **)malloc(sizeof(char *)*2)  // here 2 indicates 2 (char*)
str[0]=(char *)malloc(sizeof(char)*10)   // here 10 indicates 10 (char)
str[1]=(char *)malloc(sizeof(char)*10)   // 

strcpy(str[0],"abcdefghij");   // 10 length character 
strcpy(str[1],"xyzlmnopqr");   // 10 length character

cout<