View Compilation Error

0_0_15360833_21196.cpp: In function 'int LIS()':
0_0_15360833_21196.cpp:89:12: error: return-statement with no value, in function returning 'int' [-fpermissive]
    if(flag)return;
            ^
0_0_15360833_21196.cpp: In function 'int LDS()':
0_0_15360833_21196.cpp:112:12: error: return-statement with no value, in function returning 'int' [-fpermissive]
    if(flag)return;
            ^