View Compilation Error

0_0_29900238_7870.cpp: In function 'int main()':
0_0_29900238_7870.cpp:34:16: error: 's' was not declared in this scope
     while(gets(s)){
                ^
0_0_29900238_7870.cpp:39:23: error: 's' was not declared in this scope
     while(scanf("%s",&s)!=EOF){
                       ^