[en] Measurements are presented of the lifetimes of the B⁰, B⁰_s, Λ_b⁰, and B_c⁺ hadrons using the decay channels B⁰ → J/ψK*(892)⁰, B⁰ → J/ψK⁰_S, B⁰_s → J/ψπ⁺π^-, B⁰_s → J/ψφ(1020), Λ_b⁰ → J/ψΛ⁰, and B_c⁺ → J/ψπ⁺. The data sample, corresponding to an integrated luminosity of 19.7 fb^-1, was collected by the CMS detector at the LHC in proton-proton collisions at √(s) = 8 TeV. The B⁰ lifetime is measured to be 453.0 ± 1.6(stat) ± 1.8(syst)μm in J/ψK*(892)⁰ and 457.8 ± 2.7 (stat) ± 2.8 (syst)μm in J/ψK⁰_S, which results in a combined measurement of cτ_B⁰ = 454.1 ± 1.4 (stat) ± 1.7 (syst)μm. The effective lifetime of the B⁰_s meson is measured in two decay modes, with contributions from different amounts of the heavy and light eigenstates. This results in two different measured lifetimes: cτ_{BS⁰→J/ψπ⁺π^-} = 502.7 ± 10.2 (stat) ± 3.4 (syst)μm and cτ_{BS⁰→J/ψφ(1020)} = 443.9 ± 2.0 (stat) ± 1.5 (syst)μm. The γ⁰_s lifetime is found to be 442.9 ± 8.2 (stat) ± 2.8 (syst)μm. The precision from each of these channels is as good as or better than previous measurements. The B⁺_c lifetime, measured with respect to the B⁺ to reduce the systematic uncertainty, is 162.3 ± 7.8 (stat) ± 4.2 (syst) ± 0.1 (τ_B⁺)μm. All results are in agreement with current world-average values. (orig.)