C language learning log 10.19

One . random number

Every call rand() You get a random integer

Need to add C Several libraries of language

Two .break vs continue

break: Out of the loop

continue: Skip this round of the loop and the rest of the statements go to the next round .

They can only do to the level of the cycle where they are .

3、 ... and . Array

Data can be stored in variables , Each variable has a name , There is a type , And its living space . If we need to save some of the same types 、 Similar meanings 、 Data in the same living space , We can use arrays to hold this data , Instead of using many independent variables . Array Is a fixed length data structure , For storage Specified type The data of . There can be many data in an array , All data types are identical Of

Define an array ：

< data type > Variable name [ Element quantity ]; for example ：int grades[100];   double weight[100];

The number of elements must be an integer