View Compilation Error

0_0_15487612_20344.cpp: In function 'void cal(double)':
0_0_15487612_20344.cpp:58:26: error: 'n' was not declared in this scope
     for (int i = 2; i <= n; ++i) {
                          ^
0_0_15487612_20344.cpp:70:26: error: 'n' was not declared in this scope
     for (int i = 1; i <= n; ++i) {
                          ^
0_0_15487612_20344.cpp:75:26: error: 'n' was not declared in this scope
     for (int i = 1; i <= n; ++i) {
                          ^
0_0_15487612_20344.cpp: In function 'int main()':
0_0_15487612_20344.cpp:170:13: error: 'ans' was not declared in this scope
             ans[1] = rights;
             ^
0_0_15487612_20344.cpp:182:13: error: 'ans' was not declared in this scope
             ans[1] = lefts;
             ^
0_0_15487612_20344.cpp:194:13: error: 'ans' was not declared in this scope
             ans[1] = x;
             ^
0_0_15487612_20344.cpp:208:25: error: 'ans' was not declared in this scope
             sum += PI * ans[i] * ans[i];
                         ^
0_0_15487612_20344.cpp:212:32: error: 'ans' was not declared in this scope
             printf( "%.2lf\n", ans[i] );
                                ^