View Compilation Error

0_0_17269440_23002.cpp: In function 'int main()':
0_0_17269440_23002.cpp:6:4: error: '_int64' was not declared in this scope
    _int64 m1,m2,R1,R2,R3;
    ^
0_0_17269440_23002.cpp:8:30: error: 'm1' was not declared in this scope
    while(scanf("%I64d%I64d",&m1,&m2)!=EOF)
                              ^
0_0_17269440_23002.cpp:8:34: error: 'm2' was not declared in this scope
    while(scanf("%I64d%I64d",&m1,&m2)!=EOF)
                                  ^
0_0_17269440_23002.cpp:10:5: error: 'R1' was not declared in this scope
     R1=R2=R3=0;
     ^
0_0_17269440_23002.cpp:10:8: error: 'R2' was not declared in this scope
     R1=R2=R3=0;
        ^
0_0_17269440_23002.cpp:10:11: error: 'R3' was not declared in this scope
     R1=R2=R3=0;
           ^