Main.cc:4:1: error: expected initializer before ‘int’ int n,n1,n2,n3,n4; ^~~ Main.cc: In function ‘int main()’: Main.cc:7:7: error: ‘n’ was not declared in this scope cin>>n; ^ Main.cc:9:8: error: ‘a’ was not declared in this scope cin>>a[i]; ^ Main.cc:10:25: error: ‘n1’ was not declared in this scope if(a[i]>=0&&a[i]<=18) n1++; ^~ Main.cc:11:21: error: ‘n2’ was not declared in this scope else if(a[i]<=35) n2++; ^~ Main.cc:12:21: error: ‘n3’ was not declared in this scope else if(a[i]<=60) n3++; ^~ Main.cc:13:8: error: ‘n4’ was not declared in this scope else n4++; ^~ Main.cc:15:18: error: ‘n1’ was not declared in this scope printf("%.2f\n",n1*1.0/n*100); ^~ Main.cc:16:18: error: ‘n2’ was not declared in this scope printf("%.2f\n",n2*1.0/n*100); ^~ Main.cc:17:18: error: ‘n3’ was not declared in this scope printf("%.2f\n",n3*1.0/n*100); ^~ Main.cc:18:18: error: ‘n4’ was not declared in this scope printf("%.2f\n",n4*1.0/n*100); ^~